SALT LAKE CITY (AP) _ When Utah lost its first conference game to UNLV 72-66 last Saturday, Utah center Nate Althoff thought it was his fault.

Against San Diego State Thursday, Althoff was determined to make amends.

"I felt like I was to blame," Althoff said. "I didn't play well and coach (Rick) Majerus has really been on me this week. I really wanted to come out and make a difference tonight."

Althoff was the difference as he scored a career-high 22 points, pushing No. 21 Utah past San Diego State 83-65.

"We had no answer for Althoff in the middle," San Diego State coach Steve Fisher said.

Despite playing without Hanno Mottola, out indefinitely with sprains to his left elbow and right thumb, the Utes easily extended the nation's longest home winning streak to 49 after jumping out to a 19-5 lead.

Utah has not lost at the Huntsman Center since a 70-59 setback to Wake Forest on Dec. 31, 1996.

Althoff topped his previous career-high of 20, which he posted in Utah's 70-55 win at San Diego State on Jan. 10. The 6-foot-11 junior center dominated the paint, shooting 6-of-8 from the field and making 10-of-11 from the free-throw line.

"It was part of the game plan to go inside," Althoff said. "I really posted hard and my teammates really looked for me. With Hanno out, it puts a little more pressure on me to score more."

"You saw tonight what Nate is capable. We have confidence and we were looking for him. He really performed," Alex Jensen said.

The Utes (18-4, 7-1 Mountain West) won its 10th straight over San Diego State.

Tony Harvey made all five of his shots from the field and all three free throws in scoring 14 for the Utes. Jeff Johnsen and Phil Cullen each added 11 for Utah, which shot 54 percent in retaining first place in the conference.

"We came out with a lot of energy," said Johnsen, who started in place of Mottola. "We really wanted to see if we could play the way we wanted, not just hard enough to beat them."

The Aztecs (5-16, 0-8) did not score their first basket until David Abramowitz made a 3-pointer more than five minutes into the game. Utah's pressure defense had already forced five turnovers by that point.

Abramowitz made 7-of-9 3-pointers for 21 points while Marcelo Correa had 12 for the Aztecs.

A dunk by Phil Cullen followed by two free throws from Althoff gave Utah a 19-5 lead with 9:14 left in the first half. The Utes pushed their lead to 27-9 when Mike Puzey added a pair of foul shots.

Utah led 42-22 at halftime when the school retired Andre Miller's No. 24 jersey. Miller, who was the Cleveland Cavaliers' top draft pick in 1999, stopped in Utah on his way to the Rookie Challenge at the NBA All-Star game in Oakland Saturday.

Mottola, who missed Utah's first nine games with a knee injury, could be back on a game-to-game basis if he receives clearance from team trainer Trevor Jameson. The Utes' leading scorer is undergoing extensive tests to determine whether he will require surgery for either injury.