Fred Hoiberg needed some big wins in the transfer portal this offseason after losing the three super seniors who set the tone and helped shape the team’s much-improved culture.
With Derrick Walker gone, one of the team’s biggest needs was a new five man, and Hoiberg found his guy in Bradley transfer Rienk Mast. The 6-foot-9, 240-pound big man announced his commitment to Nebraska on April 12.
The Netherlands native averaged 13.8 points, 8.0 rebounds and 2.4 assists while shooting 51.8% from the field including 35.3% from deep and 73.6% from the free-throw line last season for the Missouri Valley regular season champion Braves. How does he fit in Hoiberg’s system and compare to Walker? Let’s dive into the tape and the numbers to find out, courtesy of Synergy Sports.
Synergy logged nearly 400 offensive possessions for Mast last season and he scored 1.010 points per possession (PPP), ranked in the 83rd percentile nationally and considered “very good.” Tack on another 70 passing possessions (he averaged 2.5 points per assist) and the points per possession plus assist climbs to 1.233. While he may be a bit undersized, he is very good at what he does and has developed into a very effective offensive player.
Mast is first and foremost a post player, logging nearly twice as many possessions in the post as any other play type (135 in total, 34% of his plays). He scored 0.963 PPP (in the 74th percentile nationally, considered “very good”) and shot 54.1% while sporting a 9.6% free-throw rate and a 13.3% turnover rate.
Mast is a physical player who works hard for seals and understands angles. He has good footwork and uses ball fakes well to find openings to score. He’s comfortable both facing up and backing his man down, and he can put the ball on the deck with confidence to work around his defender. He posts up on either block nearly equally, though he was a little more effective on the left block last season.
The thing that makes Mast so effective down low, even beyond his deep bag of tricks, is his touch and ability to score with either hand. He truly is ambidextrous as a finisher, and his go-to shot is the hook which made up 31.3% of his field goal attempts (93rd percentile). He scored 1.12 PPP on hook shots (89th percentile, “excellent”), shooting 55-of-98 (56.1%) on them.
Here is a look at what Mast is capable of in the post.
Notice the touch on some of those shots and the series of ball fakes and pivots he uses to create scoring opportunities. Also pay attention to the clips against Valparaiso and future Hawkeye big man Ben Krikke as those two will continue to battle in the Big Ten next season.
Mast is far from a black hole in the post, though. He’s a very willing and skilled passer who logged 41 passing plays in addition to the 135 scoring plays in the post. Spot-up shooters shot 11-of-22 from 3 on his passes while cutters shot 10-of-12. He does a great job of identifying open teammates, making impressive skip passes to weak side shooters as well as recognizing doubles to find teammates wide open at the rim.
Here’s a look at Mast as a passer out of the post.
Walker’s work in the post was a big part of Nebraska’s offense last season, and Mast gives Hoiberg the ability to keep running offense through the low block in the halfcourt.
Pick-and-Roll Roll Man
Mast’s second-most common play type for Bradley was the pick-and-roll or pick-and-pop (he did both plenty), accounting for 18.1% of his possessions. He scored 0.875 PPP (30th percentile, “below average”), shooting 38.3% from the field including 30% from 3 with an 8.3% free-throw rate and a 9.7% turnover rate. The film and numbers weren’t quite as kind to Mast in this area, unfortunately.
First, Mast is a little undersized and is also fairly earth-bound, which means he doesn’t offer much in the way of vertical gravity. He’s not a lob threat, and most of his rolls to the rim are of the short-roll variety where he catches just below the free-throw line and has to find a way to make a play from there. He shot 14-of-30 (46.7%) on 2-point attempts in the pick-and-roll last season.
Second, Mast is a capable 3-point shooter, but he really needs his feet to be set which limits his versatility as a shooter. He shot just 9-of-30 on pick-and-pop 3s last season.
Mast needed a certain set of circumstances to be effective in the pick-and-roll, but here’s a compilation of what it looks like when things do go right for him.
I didn’t clip assists in this category, but Mast does a good job of finding teammates out of that short-roll if the defense cuts off his path to the rim.
Bradley used Mast as a cutter on 12.1% of his plays, and though the limitations he shows in the pick-and-roll affect him in this area as well, he was a bit more effective. Mast scored 1.188 PPP (52nd percentile, “good”), shooting 63.9% from the field with a 14.6% free-throw rate and a 12.5% turnover rate.
Mast has a good feel for the floor, finding gaps to fill and making himself available when teammates suck in the defense. Again, he’s not really an above-the-rim finisher and often looks to get into his post moves off his cuts if he doesn’t have an uncontested layup. That lack of athletic pop puts a ceiling on him but his feel for the game, motor and touch still allow him to be effective in this area, as you can see below.
It’s worth noting that the dunks at the end of these last two compilations were the only two dunks he made all season long.
What makes Mast an intriguing fit for Hoiberg’s offense is his ability to space out to the 3-point line and play five-out offense as a spot-up threat, which he did on 11.3% of his possessions last season. He scored 1.333 PPP (98th percentile “excellent”), shooting 52.3% including 44.8% (13-of-29) from 3.
Again, Mast is a good spot-up shooter when he can get his feet set and shoulders squared to the basket on the catch. He also does a great job of reading how teams are defending him. If his man doesn’t close out, he lets it fly. If his man does close out, he does a good job of using pump fakes to get the defender off his feet so he can attack. If he feels his man leaning one way or the other, he takes advantage to get to the basket.
Here’s a look at some of his spot-up possessions.
In addition to his ability to stretch the floor, Mast is also capable of some of the same passes from the top of the key that Walker made for Nebraska last year. He can handle it well enough to run dribble handoff actions and has the vision and processing ability to read the defense and find cutters with on-time and on-target passes through tight windows.
Some of those passes look an awful lot like what we saw with Walker and Keisei Tominaga last year, huh? He can also put the ball on the deck to attack in true isolation sets in these situations much like Walker did, but it was a very low-volume thing for Mast last year and he was only averagely effective doing so.
The last thing we’ll focus on offensively here is offensive rebounding, which accounted for 10.1% of Mast’s offensive possessions (40 in total). He scored 1.225 PPP (71st percentile, “very good”) and shot 61.8% from the field with a 12.5% free-throw rate and a 5% turnover rate.
Again, Mast is a little undersized for the five spot but has a high motor and does a great job of pursuing the ball when a shot goes up. He’s physical in carving out space and does a good job of taking advantage of smaller players if his defender doesn’t get him boxed out early. He apparently has a 7-foot wingspan and does a good job of getting his hands on balls and tipping them around to himself or in the basket as he has good touch.
In watching Mast’s defensive clips, he certainly has some limitations that hurt him in specific areas. That being said, he played nearly 29 minutes per game for a good defensive team in Bradley (63rd in the country in adjusted defensive efficiency according to KenPom, third in the Missouri Valley; for reference, Nebraska was 69th).
The biggest area in which he struggles is his ability to change directions on the move. This weakness shows itself most often in how he defends spot-up situations. He has a tough time closing out to shooters quickly enough to bother the shot, and if he does so he struggles to slow down and stay in front if his man attacks his closeout. That being said, Bradley had some length and weak-side rim protection around him that helped cover when Mast chased his man off the line. He’ll often help off his man one pass away and give up easy kicks for jumpers, but it’s hard to say if that’s on him or just Bradley’s defensive scheme.
Speaking of Bradley’s scheme, it asked Mast to show hard on every ball screen before recovering to his own man. He was actually pretty good at it, routinely cutting off the ball-handler and containing the action. However, it’s asking a lot of him to do that and also recover out to shooters if the screener pops, which is where he ran into trouble (especially since Bradley didn’t really send a help defender to give him time to recover). Between spot-up and pick-and-pop situations, opponents shot 40.4% from 3 against him, which is also some rough shooting luck. He works hard to recover against screeners that actually rolled to the rim instead of popping and did a good job defending those plays.
In fact, “works hard” describes Mast’s defense overall. He gives tremendous effort and Bradley asked a lot of him. He isn’t the fleetest of foot but works hard to slide as best he can and keep his man in front of him.
In the post, he generally does a good job of anchoring and holding his ground (we’ll have to see how he holds up in that area against Big Ten big men). He works hard to slide his feet and keep his body between his man and the basket to force a more difficult shot over the top of his outstretched arms, and he does a solid job of challenging vertically.
Here’s a look at some clips that showcase the positive traits I described above.
Mast isn’t a dynamic rim protector or a huge space-eater, but he generally works hard on the defensive end and executes what the scheme asks of him.
Overall, the film shows a guy who might be a perfect fit for what Hoiberg wants to do. He brings some of the same skills that Walker did to the five spot but adds a different dimension with his ability to shoot out to the 3-point line. It’s always difficult to make the leap from mid- to high-major, but Mast has a solid baseline of skills that should make him a major asset for Nebraska next season.
Jacob Padilla has been writing for Hail Varsity since 2015. He covers football, volleyball men’s basketball and prep sports. He also co-hosts the Nebraska Preps Postgame and Nebraska Shootaround podcasts for the Hurrdat Media and Hail Varsity podcast networks. His love of basketball can best be described as an obsession and if you need to find him, he’s probably in a gym somewhere watching, coaching or playing hoops.