Dowell's departure leaves freshman Cezar Guerrero as the lone point guard on the Cowboys' roster.
Dowell started the team's only game, a loss to Alabama, following Gulley's departure on Dec. 20.
The reasons for Dowell's exodus are not known at this time but it is unlikely a playing time issue with him now only sharing minutes at the position with Guerrero. Playing time was cited as the primary reason for Gulley leaving the team.
Dowell had played in 21 straight games for the Cowboys, starting 10 of those contests. He was averaging 5.5 points in just over 19 minutes per game so far this season.
It is likely Keiton Page will have to shift back to playing some at the point, as he did at point last season when Gulley was injured and Dowell was the lone point guard.
With Dowell's decision to leave, OSU now has zero players remaining from coach Travis Ford's vaunted 2009 recruiting haul. That class included Gulley and Dowell, as well as, Karron Johnson, Jarred Shaw, Roger Franklin, Torin Walker and Ray Penn.
Johnson never made it to campus but the rest of the class has all left since arriving and playing in Stillwater.
Ford will be pressed to figure out new roles and rotations as the schedule isn't getting any easier in the next few weeks. OSU plays SMU in Dallas on Wednesday before returning to Stillwater for a meeting with Virginia Tech on New Year's Eve. Then conference play begins with Texas Tech on Jan. 4, at Texas on Jan. 7, Oklahoma on Jan. 9 and at No. 6 Baylor Jan. 14.