College basketball likely will have a new No. 1 team next week.
It was top-ranked Auburn's first loss since a double-overtime defeat to UConn on Nov. 24.
The victory was especially sweet for the Razorbacks, who said afterward that they took exception to the Tigers dancing on their logo during pregame warm-ups.
"We didn't like them dancing on our logo," said Jaylin Williams, whose late basket forced the extra session. "That was disrespectful to us. That added fuel to the fire.''
With Auburn going down, it likely opens the door for Gonzaga to move back to the No. 1 spot in next week's AP Top 25. The Bulldogs opened the season atop the rankings, but dropped following losses to Duke and Alabama in late November and early December. They regained the No. 1 position for one week last month, but Auburn passed them and stayed at No. 1 for the past three weeks.
Gonzaga hosts Pacific on Thursday and Saint Mary's on Saturday; if the Zags win both, they will likely go back to the top spot.
"I was proud of being No. 1," Auburn coach Bruce Pearl said. "Gosh, we haven't lost since sometime in November."
Pearl added: "We understand we have a price on our head. It's very difficult on the road. We worked really hard to put ourselves in this position. It was tough.''
Arkansas led by as many as 12 points early in the game, but the Razorbacks didn't make a field goal for the final 8 minutes, 28 seconds of the first half, allowing Auburn to cut the lead to three entering the break. The two teams traded baskets for most of the second half, with Auburn taking a five-point lead with 2:40 left following seven straight points from Wendell Green Jr.
But Arkansas responded with five straight points, and then Williams answered Green's go-ahead basket with a tying basket with 23 seconds left. Green's 30-footer in the final seconds of regulation didn't fall.
In overtime, Auburn opened the scoring with an Allen Flanigan layup -- but Arkansas owned the extra period. The Razorbacks went on a 7-0 run in the final two minutes and made four free throws in the final 30 seconds to put the game away.
After the final buzzer sounded, several Razorbacks players hopped onto a table as fans stormed the court to join the celebration.
"There won't be a better crowd than that in the next 50 years," Arkansas coach Eric Musselman said. "Nobody that was here did not have fun unless maybe an Auburn fan."
Arkansas won its ninth straight game, improving to 19-5 overall and 8-3 in the SEC. The Razorbacks head to Alabama on Saturday, while Auburn will look to bounce back at home against Texas A&M.
Tuesday's victory was Arkansas' first win over an AP No. 1 team since 1984, when it knocked off a North Carolina team featuring Michael Jordan and coached by Dean Smith.
According to ESPN Stats & Information research, Arkansas has won 12 of its 20 home games against AP top-five opponents in the AP poll era (since 1948-49). That's the second-best winning percentage of any program, behind only Kentucky.
The Associated Press contributed to this report.