Maclin will hold a news conference at Missouri's Columbia campus on Friday morning to announce his decision, according to media reports.
During the regular season, Maclin said he would remain at Missouri unless he were projected as a first-round pick. Todd McShay of Scouts Inc. has Maclin going in the first round in his most recent mock draft, while Mel Kiper Jr. rates him No. 2 among all junior and redshirt sophomore wide receivers.
However, following Missouri's Alamo Bowl victory, Maclin said: "There's a lot more that I want to achieve at this university."
Maclin caught 102 passes for 1,260 yards and 13 touchdowns in 2008 for the Tigers.