UPDATED, 11:40 p.m.

COLUMBIA, MO. • This time, Missouri didn’t even get two minutes out of Michael Porter Jr.

After sitting for most of Friday’s season-opener against Iowa State, the preseason All-American was held out of Monday’s game against Wagner as the team’s medical staff evaluates what coach Cuonzo Martin confirmed as a leg issue after the Tigers’ 99-55 victory.

Porter not only didn’t play Monday, but he didn’t sit on the bench with his teammates during the game. Porter spent the game in the locker room resting his leg.

Martin declined to elaborate on the severity of Porter’s condition and was unsure if the freshman will travel with the team to Thursday’s game at Utah.

“I don’t know how serious it is,” Martin said. “It’s hard for me to say that. But I think it’s day to day. That’s the best assessment for me to say right now: It’s day to day.”

“I understand you want that information,” Martin continued. “The truth of the matter is I’m not a doctor. I can’t give you more than that. I don’t want give you more than that. It’s not my job to give that out of respect for Mike and his family. So I think the best thing is (saying) day to day. If I had more I’d give you more.”

After playing the best game of his young career, freshman forward Jontay Porter wasn’t sure when his older brother will return to the lineup.

“I’m sure as you can imagine any player would be upset that they don’t get to play their first year of college,” Jontay said after finishing with 11 points, eight rebounds and four assists in 21 minutes off the bench. “But he’s handling it well. He’s rehabbing. He’s day to day now. Hopefully he’ll be ready the next game, but we’ll see. There’s no telling.”

Just like Friday’s win over the Cyclones, the Tigers didn’t miss their most celebrated player in another one-sided matchup. Kassisus Robertson, Missouri’s graduate transfer point guard, bounced back from a rough shooting night in Friday’s game and led the Tigers (2-0) with 23 points. Robertson missed nine of 12 shots against Iowa State but came back Monday with the perimeter scoring threat the Tigers expected when he transferred this summer. He made seven of 10 shots Monday, including five of eight from 3-point range. Robertson is still making a sudden adjustment from shooting guard, the position he’s played throughout his college career.

“Anytime he shoots the ball we expect it to go in when he gets his shoulders squared,” Martin said. “I wasn’t worried about him. When he’s open he needs to let it fly.”

In MU’s highest scoring game since last year’s opener against Alabama A&M, a 99-44 win, four of Robertson’s teammates scored in double figures: Jordan Barnett with 13, Kevin Puryear (12), Jontay Porter (11) and Terrence Phillips (10).  

“To be completely honest we’ve got a lot more weapons on this team than last year,” Barnett said. “We can spread the floor all the time and there’s almost times I can just stand in the corner and get a couple shots.”

Jontay put together a dazzling first half off the bench with nine points, seven rebounds and four assists in 13 minutes. The 6-11 freshman created second-chance points on consecutive possessions midway through the half, first with a putback on a missed Barnett 3-pointer. On the next trip down the floor, Porter chased down a missed Robertson 3-pointer, zipped a pass back to the point guard and watched him bury his second attempt behind the arc. Robertson led all scorers with 13 points in the first half, including a 3-pointer at the final buzzer, good for a 54-21 halftime lead.

The only bad news for the Tigers in the first half came with 5:55 left when freshman guard Blake Harris went down under the basket and had to be helped off the court. He sat at the end of the bench for the rest of the game with an ice pack on his left knee. Martin said he’d know more about Harris’ status Tuesday.

After a strong 14-point performance in Friday’s win, freshman center Jeremiah Tilmon spent most of the night on the bench as fouls turned him into a spectator for all but 10 minutes. Tilmon scored six points in the game’s opening minutes on a putback and two post-up moves but drew his fifth foul with 11:09 left in the game. He finished with seven points and two rebounds. Tilmon also fouled out in two of MU’s three exhibition games.

“He plays with a high level of energy,” Martin said. “Once he gets that all figured out he’ll be extremely tough because he’s so big and physical and he keeps coming.”

Blake Francis led Wagner (1-1) with 17 points.

With his brother in the locker room and Tilmon on the bench most of the night, Jontay Porter saw extensive playing time and rarely looked like a 17-year-old who should be starting his senior season at nearby Father Tolton High School. In the second half, the 6-11 freshman stole the ball near the 3-point arc and handled the rest on his own, driving in for one-handed floater in traffic.

Through two games, Jontay has the upper hand on his brother on the stat sheet, scoring 16 points to Michael’s two. Jontay, who turns 18 on Wednesday, said he’s been wondering how long it’ll take Michael to catch up with his numbers

“I’m sure it’ll happen eventually being the player that he is,” Jontay said. “It might be the next game where he comes out and scores 50 points and surpasses me in one game. I’m looking forward to playing with him.”

But when? Maybe Thursday. Maybe not. 

• The Tigers’ last highlights came in the final minutes when the student section chanted for walk-on Adam Wolf, whom Martin quickly called to the scorer’s table, then watched him knock down a 3-pointer, the second of his career. Brett Rau, another walk-on, drilled a 3-pointer in the closing seconds.

"That was the highlight of the night for me," Robertson said. "Those guys are with us every moment, every moment through practice. They work just as hard as us."

Martin wasn't exactly thrilled with the walk-ons late cameos. 

"They can make shots," he said. "I didn’t think they defended as well. That’s the truth of the matter. We treat them all the same. It’s not, 'This guys is a walk-on. This guy’s on scholarship.' It’s all the same when you step on the floor. You get an open shot you take it but you’ve got to defend and rebound. I thought Brett had two breakdowns on block outs and Wolf didn’t get back defensively like he needed to. It’s all the same. It doesn’t change."

• Also out of the lineup Monday were freshman guard C.J. Roberts and sophomore forward Mitchell Smith, both of whom Martin plans to redshirt this season. Smith tore his anterior cruciate ligament last January and missed the rest of the season. He appeared in 11 games last year and averaged 2.4 points and 1.7 rebounds.  

Dave Matter is the Mizzou beat writer for the St. Louis Post-Dispatch.