EAGLE — The race for the 5A Southern Idaho Conference regular-season championship just got a lot more complicated.

Eagle drove the length of the field in the final minutes to secure a 31-29 upset of previously unbeaten Rocky Mountain on Friday night at Thunder Stadium.

Eagle, Rocky Mountain and Borah are tied for first in conference play at 6-1.

“I still think there is a lot of football to go,” Eagle coach Paul Peterson said. “The next couple of weeks are going to be a wild ride.”

Eagle’s game-winning drive was quite the ride, too.

Junior quarterback J.T. Williams guided the Mustangs 82 yards down field in the final 1 minute, 52 seconds, setting up senior Layne Leisten’s 22-yard field goal.

Once the Mustangs reached Rocky Mountain’s 5-yard line with 1.7 seconds left, Eagle called a timeout, which was followed by a Rocky Mountain timeout.

The waiting didn’t faze Leisten, a first-year kicker.

“I just believed in myself and I believed in my team,” Leisten said. “The big thing is my team got us there. Great coaches. Everybody. It wasn’t about me kicking the field goal, it was about our team getting me in that position.”

His teammates never doubted him, either.

“He kicks it every time. He doesn’t miss,” Williams said. “I knew he was going to make it.”

Rocky Mountain held a 16-14 lead at halftime, and neither team was able to score in a third quarter that featured just three combined first downs.

The floodgates opened in the fourth quarter, with each team scoring a pair of TDs.

“Eagle played real well. Give them credit, they did what they were supposed to do,” Rocky Mountain coach Jason Warr said. “A few plays here and there. We had some chances maybe to finish some drives in the third quarter and we didn’t. … How we answer that is what’s on our plate.”

Eagle has games remaining against Mountain View and Timberline, while Rocky has yet to face Centennial and Borah. The top four teams in the 5A SIC advance to the state playoffs.