Look at last year's draft:
Of the 30 players selected in the first round, only 5 were college seniors, which, at most schools, puts you at 21 or 22 years old.
2015 draft: 4 seniors in the first round
2014 draft: 5 seniors in the first round
2013 draft: 3 seniors in the first round
2012 draft: 4 seniors in the first round
So in the past five years, of a total 150 first-round draft picks, only 21, or 14% of all first-round picks were Mika's age. Age absolutely makes a difference when it comes to draft pecking order. When given the choice between a 19 year old freshman or a 23 year old junior with similar athleticism and skill sets, a team will take the younger guy first almost every time.