While fellow freshman Derrick Walton Jr. and Zak Irvin were getting quality minutes on the Wolverines' Big Ten championship team, Donnal spent his season developing his 6-foot-9 frame. And is now listed at 230-pounds on the school website.
The added muscle may help Donnal earn some playing time next season, said U-M coach John Beilein.
"Mark is still 18-years-old right now," Beilein said. "So that is very encouraging to us. Every day when our guys were out shooting around – he was finishing a lift with (strength coach) John Sanderson in the weight room.
"What I like about Mark, is he takes coaching and move it right away. When in doubt, he shoots it and it goes in. And he's got great instincts as he learns other parts of the game. Depending right now on a lot of different things – he may have an opportunity to play next year. Will have to see how it all shakes out."
Confidence grows with Walton Jr.
Walton, who averaged 7.9 points, 2.9 assists and started 36 games at point guard last season, made major growth throughout his freshman season and has earned the full "confidence" of Beilein.
"I have so much confidence (in Walton)," Beilein said. "His workout yesterday was excellent. I have so much confidence, that his game continues to be an easier one for him to dissect and see, as he plays at this level."
And with the possibility of Michigan losing some players to the NBA, Beilein expects Walton to more of scorer next season.
"I think he is guy we can play through more than we did this year." Beilein said. "Obviously, Nik (Stauskas), Caris (LeVert) and Glenn (Robinson III) we played through more this year. They had over 300 shots all three of them. That's something Derrick is going to want to do. I sense Zak Irvin as well is going to be guy who is going to make steps this year."
Michigan played one of the toughest non-conference schedule's in the country in 2013-14 season. And next season could be even tougher, says Beilien.
That's hard to imagine, considering the Wolverines played NCAA tournament teams Iowa State, Arizona and Duke in non-conference play.
"Our schedule I thought last year I think it turned out to be very difficult and very challenging and very appropriate for what we needed," Beilein said. "I think this one will be even more challenging."
Beilein said the Wolverines expect to play in a pre-season four-game tournament, host an ACC-Big Ten Challenge opponent and will travel to Arizona to finish a home-and-home with the Wildcats. The scheduling doesn't stop there, Beilein noted they would like to add another premium school to strengthen their 2014-15 schedule as well.
However, the major obstacle facing the Wolverines is getting a high-major program to give up a home game, says Beilein.
"Ideally you'd like to have two great home games and two great away games," Beilein said. "and it never goes away. But it's really hard to do. The day of saying ‘hey' calling up saying another major and saying ‘Hey, let's go home and home?' It's really hard to do, because there is not too many people that can afford to leave their place if they're packing their place and give up that payday."