Oregon (18-8, 9-5 Pac-12), which took a 40-37 lead into the locker room at halftime, held the advantage for most of the second half, stretching is lead to as many as eight points with 5:38 to play.
Cal used a 10-2 run over the next 3:57 to tie the game up at 75 all with 1:41 to play. Cobbs contributed six points during the spurt. The Bears then took their first lead of the second half with a Jorge Guttierez successful free throw to pull ahead 76-75.
Cal then followed an Oregon basket with a three-point play by Harper Kamp to regain the advantage and the Bears never looked back en route to the victory.
With Cal holding a three-point lead, the Ducks had one final chance but Devoe Joseph's three-point shot missed as time expired and the Bears sealed the come-from-behind win.
Cobbs led the charge with his 28 points to go along with eight assists and zero turnovers in the contest. Kamp poured in 20 points and was active on the glass with six rebounds for the Bears.
Joseph led Oregon with a career-high 33 points for the Ducks.
Cal will close its home schedule on Saturday against Oregon State inside Haas Pavilion at 7 p.m. as the program honors its seniors Gutierrez and Kamp.