BERKELEY (AP) – Opposing teams have tried just about everything to stop top-ranked Oregon’s high-speed offense without much success.

A new tactic might be emerging: faked injuries.

Oregon’s fans have been clamoring over perceived fake injuries all season, even booing opposing players they believe are trying to kill the Ducks’ tempo by lying on the ground.

One instance came in Oregon’s 15-13 win over Cal on Saturday, when Bears defensive lineman Aaron Tipoti got up from a play, looked to the sideline and fell to the ground, holding his leg.

Cal coach Jeff Tedford blamed the fall on cramps, saying those happen often in up-tempo games.

Pac-10 officials say there’s not much that can be done because officials can’t tell if someone is injured or faking.

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