MSU's Derrick Harmon, previously in transfer portal, reentered after a turbulent season.
Rejoined Spartans under Jonathan Smith, then back in portal in April.
Deion Sanders eyes Harmon for Colorado Buffaloes, impressed by his 40 tackles.
Sanders' staff is active in Michigan recruiting, making moves in high school cycles.
Harmon considering Buffs' spring game visit; Colorado seeks portal replacements.
Elite run-stopper Harmon attracts interest; USC's Lincoln Riley also in pursuit.
Harmon, Detroit native, not highly touted recruit but gained attention at MSU.
Transfer portal asset Harmon could make a significant impact for Buffaloes or Trojans.