CORVALLIS, Ore. -- Kianna Ibis had 28 points, 13 rebounds and three blocks as No. 19 Arizona State handed No. 10 Oregon State its first Pac-12 loss, 79-76 in double overtime on Sunday.
Reili Richardson added 16 points, including nine in the overtime periods, and made three of four free throws down the stretch to seal the upset for the Sun Devils (13-5, 4-3 Pac-12).
Mikayla Pivec had 19 points, nine rebounds and seven assists and Katie McWilliams added 12 points for the Beavers (15-3, 5-1).
Richardson made a layup to tie the game at 66 near the end of the first overtime.
Arizona State led 73-72 with a minute left in the second overtime when Richardson sank a scoop with 33.3 seconds left. Pivec and McWilliams both missed shots that would have tied it in the final 20 seconds.
Oregon State shot 37 percent and went 10 for 27 on 3-pointers, while Arizona State shot 46 percent, including 5 for 17 from long range.
The teams went back in forth the last minutes of the fourth quarter, the first overtime and the second OT.
Ibis made a foul-line jumper with 6.8 seconds remaining in regulation to put the Sun Devils ahead 60-58, but Pivec made a lay-in with 2 seconds left to tie it.
Arizona State: The Sun Devils went 2-2 in a four-game stretch against ranked teams, three of them in the Top 10. Things look a bit easier in the next weeks, but the competition is deep in the Pac-12.
Oregon State: The Beavers had won 13 straight games at Gill Coliseum, where they are now 70-8 since the start of the 2014-15 season.
Arizona State: Hosts UCLA on Friday.
Oregon State: At Washington on Friday.
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