Coach Rich Rodriguez made the announcement after Saturday's spring game.
"Unfortunately, it is an ACL tear, which just makes me sick because he is such a great player, but he still will be," Rodriguez said. "It wasn't an ACL, MCL and all that. It was just an ACL, but with that said, he will have surgery as soon as possible and get going on rehab. I don't know the timeframe for him being back. But the way technology is today, he will be back bigger and stronger. I really felt bad for him but our guys will bounce back. Austin is a tough, strong guy and he will bounce back."
The Wildcats' offense already had question marks trying to replace quarterback Matt Scott -- last year's Pac-12 leader in total offense. Hill, a Biletnikoff semifinalist who had 81 catches for 1,364 yards with 11 touchdowns, headlines a talented wide receiver group for the Wildcats. Along with running back Ka'Deem Carey, the nation's leading rusher last season, Hill was expected to be a key cog in the Wildcats' attack.
The Wildcats not only lose a potential All-American, but also a versatile athlete who could play all of Arizona's receiver positions.
"It's a host of guys," said Rodriguez, when asked who might fill in for Hill. "We have the guys we have now and we always have a great group of guys coming in the fall that can play well at wide receiver. We want to get eight to nine guys ready at that position. We didn't have that many last year so our hope is for this year. When Austin comes back he'll add that to the mix."