SAN DIEGO -- San Diego State's 10-game winning streak to open Mountain West Conference play seemed all but over when New Mexico took a five-point lead with 21.1 seconds to play.

Remarkably, the Aztecs forced overtime and then won it 78-71, tying the MWC record for the best start at 11-0.

No shot was bigger than Malik Pope's 3-pointer with 6.6 seconds left in regulation, following a New Mexico turnover, that tied it at 66.

That turnover was a source of controversy after the game, as the official who was covering the Lobos' inbounds play with 12.9 seconds remaining ruled the New Mexico player had not established out-of-bounds status before receiving the ball. The resulting turnover gave the ball to San Diego State.

New Mexico coach Craig Neal said he didn't get a good explanation on the inbounds play.

"I will take it on me," Neal said. "We had a great inbounds play, and there was a call that was made and, right or wrong, if it's close, you can't make that call. I'll just say that. I thought our guys played their butts off. It was a very competitive game."

The Mountain West issued a statement after the game that said careful review of slow-motion video replays showed the call to be incorrect. 

"The New Mexico player did get one foot down [two feet are not required] out-of-bounds before receiving the ball, thus establishing his location in accordance NCAA Basketball Playing Rules 4.23.1.a and 7.1.1. By rule, the officials were not permitted to go to the monitor during the game to review this play." 

"We've practiced that play 100 times. My kids were demoralized in overtime," Neal told ESPN's Andy Katz. "If we beat San Diego State, we are 8-2 and get them back at home. That call could cost me a conference championship."

San Diego State coach Steve Fisher told Katz that while the Aztecs benefited from the call, "if we go back and slow-motion every close call, there would be more than one call ruled incorrect.

"This was a hard-fought game and I feel bad that there is now controversy. The official who made the call is a terrific ref, and I feel Craig Neal would agree. It certainly is a very tough way to lose."

Pope couldn't get too excited following his game-changing 3. "We had to make sure they didn't get a quick bucket down the stretch," the sophomore forward said.

New Mexico didn't get off a shot before the buzzer. Jeremy Hemsley then scored eight of his 23 points in overtime, including a go-ahead jumper in the key with 1:05 left in the showdown of the conference's top two teams.

The Aztecs improved to 18-6 overall. At 11-0, they're off to their best start to a conference season. SDSU senior forward Winston Shepardscored 15 points and Trey Kell had 12.

During a timeout, associate head coach Brian Dutcher told Fisher to put in Pope to give the Aztecs another 3-point shooter. Pope was supposed to look for Kell, but when he didn't get to his spot in the corner in time, Pope popped in the tying 3.

"The play was not designed for Malik to shoot," Fisher said. "Before we broke the huddle, Dutch said, `Malik, if they back off of you and you're unguarded at the 3-point line, shoot it in.' So Dutch should get some kudos on that one."

With Kell taking too long to get to his spot, "I let the ball go," Pope said. "It felt great to make that shot."

Said Neal: "You can't let a guy have a 3 without putting a hand up. That was just a mental mistake that we just didn't do. That's on me."

New Mexico (14-9, 7-3) jumped to a 71-68 lead with 2:10 left in overtime before Hemsley, a freshman point guard, and the Aztecs took over.

Hemsley, who made a jumper on SDSU's first possession of OT, hit a go-ahead shot from the key to put the Aztecs ahead for good at 72-71 with 1:05 left. After Winston Shepard made a layup with 28.7 seconds left, Hemsley sealed it by making four free throws.

The Aztecs tied the 2003-04 Utah Utes for the best start to a Mountain West season.

New Mexico's Elijah Brown also scored 23 points, including making 12 of 14 free throws. Tim Williams scored 21.

San Diego State's Skylar Spencer had 8 points and 10 rebounds, and came up big on both ends of the court during a span of just more than a minute that seemingly put the Aztecs in control.

With the Aztecs trailing 39-38, Spencer made a bank shot with 13:01 to go. He then blocked consecutive shots by the Lobos before making a slam dunk for a 42-39 lead. Spencer got his hand on another shot just seconds later.

Spencer had a nice reverse layup during a run that helped give the Aztecs a 48-41 lead with nine minutes to go. But the Aztecs cooled off, including missing several 3-point shots, and the Lobos slowly closed the gap until Adams hit his go-ahead 3.

TIP-INS

New Mexico: The Lobos have lost four straight at SDSU's Viejas Arena.

San Diego St.: The Aztecs have won 13 straight MWC games dating to last season.

UP NEXT

New Mexico plays at Utah State on Tuesday night.

San Diego State is at Fresno State on Wednesday night.

ESPN's Andy Katz and The Associated Press contributed to this report.