Look at the 24/7 UConn player rankings. Here are UConn's 3 lowest rated recruits: Lwal Uguak, Elijah Jeffreys, and Kevon Jones.
Uguak shows up as the lowest possible 2*, but he is rated by Canada Football Chat as the #6 recruit in Canada. Jeffreys played QB in high school, and was a Boston Globe All-Scholastic at QB, but will come to UConn as a WR. His track times are 6.65 sec in the 55m and 11.21 sec in 100m at 6'4", 190 lbs. Jones was the Courant Defensive Player of the Year and a unanimous Connecticut All-State football player.
I think all 3 could be major contributors at UConn, but they fell through the 247 recruiting cracks.