Tennessee rookie receiver Brandon Jones sprained his right knee and went down to the grass as he was trying to turn back for a pass just before halftime Sunday. San Francisco cornerback Shawntae Spencer picked off the pass intended for Jones and ran 61 yards for a touchdown with 27 seconds left in the second quarter. Jones had sprained the same knee last month and missed a game. He was able to walk off by himself, but went straight to the locker room. He was not on the sideline at the start of the third quarter, and a team spokesman said Jones sprained his right knee, with his return questionable.