Atlanta United finished a whopping 34 points behind Lionel Messi and star-studded Inter Miami during the regular season.

Now, the Five Stripes have a shot at pulling off a stunning upset of the best team in Major League Soccer.

Xande Silva scored with about a minute to go in stoppage time shortly after a goal by Messi was waved off by a clear offside, giving ninth-seeded United a 2-1 victory over Miami on Saturday night to even the best-of-three MLS playoff series at one game apiece.

"We've been the so-called underdogs every week," said Derrick Williams, who scored Atlanta's first goal. "We're in fight-or-flight mode, and we're definitely fighting."

United managed a wild-card victory at Montreal on penalty kicks just to get a shot at the Supporters' Shield winner, which set an MLS regular-season record with 74 points.

United finished with just 40 points — the fewest of any playoff team — and didn't earn its postseason spot until the final day of the regular season.

None of that mattered when Silva blasted a right-footed shot into the top left corner to beat goalkeeper Drake Callender in the 94th minute.

The Atlanta player celebrated by ripping off his shirt and dancing in front of the supporters section at Mercedes-Benz Stadium while the announced crowd of 68,455 cheered.

"I saw space there and then, boom!" said Silva, who came off the bench in the 89th minute.

Messi had plenty of good scoring chances but only found the back of the net with the flag raised for offside. Atlanta United took off the other way for Silva's game winner.

"I was thinking, 'Please be offsides,'" Williams said with a smile. "He didn't time his run right."

United rallied from a 1-0 halftime deficit, the result of a huge error by keeper Brad Guzan, to force a decisive game next Saturday night in South Florida.

"The truth is that we came to win," Miami defender Tomás Avilés said through a translator. "But now there is the possibility of playing one more game, so we are very calm that it will be decided at home."

Miami coach Tata Martino, who guided Atlanta United to the MLS Cup title in 2018, bemoaned his current team's lack of a finishing touch.

"We did a lot to deserve to win the game," Martino said. "We're weren't sharp in front of the goal and Atlanta, with fewer chances, fewer approaches and less control of the game, ended up taking it in the end."

Williams tied the match in the 58th minute after a corner kick was turned away by the Herons. Pedro Amador sent a cross back into the box from long range and Williams dove to get a head on it, skipping it past Callender.

Messi misfired on at least three shots, going wide a couple of times before blasting one over the net in the 83rd with Miami pressing for the go-ahead goal. He walked away rubbing his beard, clearly frustrated at his lack of accuracy.

"Keeping him quiet is massive," Williams said. "He's the best player to ever play."

Guzan's blunder handed Miami the opening goal in the 40th minute.

After easily grabbing a cross into the box, Guzan went to boot the ball away — only to stumble and loose control with Miami's Federico Redondo running along beside him. Redondo sent the free ball to David Martínez, who casually flicked it over four United defenders into the unguarded goal while Guzan looked on helplessly.

The 40-year-old keeper claimed he was interfered with by Redondo, but the replay appeared to show Guzan tripping himself up.

In the 89th, United missed a prime chance to grab the lead when Saba Lobjanidze rocketed one off the crossbar. Bartosz Slisz collected the ricochet, but fired it over the net.

Silva made sure it didn't matter.

UP NEXT

Miami won the opening game of the series 2-1 at Chase Stadium. But Atlanta won at Fort Lauderdale during the regular season, pulling out a 3-1 victory on May 29.

"We beat them there. They beat us there," Williams said. "Let's go."

The winner of Game 3 will advance to the conference semifinals against the team that emerges from the Orlando-Charlotte series, which also is tied 1-1.