Nation's biggest talent upgrades

Emmanuel Mudiay, ESPN's No. 5 overall recruit, should immediately contribute at Southern Methodist. Mike DiNovo/USA TODAY Sports

College basketball rosters throughout the country are revamped each season because of player departures. Graduation, transfers and the possibility of entering the NBA draft all drain talent from programs. Who fills those spots? More often than not, it's freshmen.

Though talented, these newcomers are typically hard to count on early. Their bodies aren't physically ready for collegiate competition. They aren't mentally prepared for the grueling schedule of class, practice and games.

Relying too much on freshmen could be a risky proposition, and Insider's Seth Greenberg will look at programs that could be particularly freshman-dependent Friday. But there is no denying when the right freshmen commit to your program, it could make a huge difference in raising a team's talent level. This season there are a select number of programs where the incoming talent is more beneficial to long-term success than the player or players who left the program. Here are five instances where that's the case.

Southern Methodist Mustangs
Key outgoing players: Nick Russell, Shawn Williams
Incoming talent: Emmanuel Mudiay (No. 5 in ESPN's 2014 recruiting rankings)

SMU coach Larry Brown told me last season he thought Russell was one of the best defenders in the American Conference ... and country. Production from both former transfers (Kansas State and Texas, respectively) will be missed in 2014-15.

But even with these key losses, the Mustangs will be better next season. When you combine one of the nation's elite recruits -- a true difference-maker -- with a roster laced with experience and a Hall of Fame coach, it's easy to see why they'll make a jump. Mudiay, a big (6-foot-5) lead guard, thrives in transition and puts pressure on any defense. When the game slows down, he can utilize his power and size to attack the hoop and either score or dish. He's also added a low-mid post game, which is incredibly valuable to post up smaller guards.