AP Sports Writer
SAN DIEGO (AP) - Following its worst performance in the shot-clock era, No. 15 New Mexico isn't running away with the Mountain West Conference race anymore.
JJ O'Brien had 12 points and 10 rebounds, Jamaal Franklin added 10 points and San Diego State routed the Lobos 55-34 on Saturday to hand them their first conference loss.
New Mexico's 34 points were its fewest since scoring 32 on Jan. 31, 1976, at Utah, and its 25 percent shooting (11 of 44) was its worst mark since at least 1965.
"We weren't who we were," coach Steve Alford said. "We didn't execute our offense. We really got dominated inside, which we thought would be our strength. They beat us points in the paint; they beat us on the glass. They took away just about everything that was our strength.
The Aztecs (16-4, 4-2) won their second straight game. The Lobos (17-3, 4-1) had their four-game winning streak snapped.
Kendall Williams scored 14 points for the Lobos.
New Mexico's previous season lows of 46 points and 31.8 percent shooting came in its last loss, 60-46 at Saint Louis on Dec. 31.
SDSU shot only 40.4 percent (23 of 57) but outrebounded the Lobos 41-26.
"I give them a lot of credit for what they did defensively," Alford said. "But we've usually been much more poised than that. We've been a very good road team, and hopefully we'll continue to be a very good road team. But they took us out of a lot of things. We talked about wanting to work to get good shots, and I just didn't think we did that today."
SDSU and New Mexico shared the MWC regular-season title last year, with each team winning at the other's arena. The Lobos then beat the Aztecs in the conference tournament championship game.
The Aztecs fell out of The Associated Press Top 25 on Monday after losing at home to UNLV and on the road to Wyoming last week. SDSU bounced back by winning at Nevada on Wednesday.
Leading 33-19 at halftime, SDSU scored 10 of the first 15 points in the second half to go up 43-24. O'Brien had six of those points, including a nice reverse layup after rebounding DeShawn Stephens' missed free throw. O'Brien also scored after rebounding his own miss and on a jumper.
San Diego State ended the first half on an 8-0 run, including a 3-pointer by Franklin.
After a slow start by both teams, the Aztecs took control with a 14-2 run that gave them a 21-9 lead with 9:19 left before halftime. That run also ended with a 3-pointer, by Xavier Thames.
Thames, who's been bothered by a back injury, didn't start for the fourth time in six games. Freshman Winston Shepard had five points during the 14-2 spurt.
New Mexico came back with a jump hook by Alex Kirk and a 3-pointer by Tony Snell to make it 23-14. New Mexico didn't make a field goal the rest of the first half after Cleveland Thomas hit a baseline jumper with 4:53 to go.
"You can't question our defense," New Mexico guard Hugh Greenwood said. "We kept this team to 50-odd points in their building. Normally you're going to win a lot of games. Keep them to 50-some points and not even being in the game, there has to be something with the offense."
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