Twins sweep Diamondbacks as Max Kepler, Matt Wallner homer in both of the ninth

It took more than three months for Matt Wallner to crack a regular role in the Twins lineup, but now it's hard to imagine where they would be without him.

Wallner, who was on the wrong side of a roster crunch until his performance couldn't be ignored any further, crushed a walk-off, two-run homer off the front of the second deck in center field to give the Twins a 5-3 victory over the Diamondbacks on Sunday and seal a three-game sweep at Target Field.

It was Wallner's sixth homer in 11 games, but his first walk-off hit, and it gave his team a season-best 4½-game lead in the AL Central over the Guardians. Wallner raised his right arm as he rounded first base, and his teammates drenched him with water from two coolers as he touched home plate.

"He's been killing it all year," Carlos Correa said of Wallner, who has a .954 OPS in 30 major league games. "He's been a big boost to our lineup. It was great to see him hit that walk-off, man. That was pretty special."

Wallner's 415-foot homer off closer Paul Sewald capped a chaotic ninth inning. The Twins (59-54) trailed by a run after Christian Walker lined a solo home run off Caleb Thielbar with one out in the top of the ninth. On the first pitch of the bottom of the inning, Max Kepler walloped a tying homer that landed in the second deck in center field.

It was the sixth time Sewald pitched against the Twins since the All-Star break, as he was traded from Seattle to Arizona last week. Wallner faced him only once beforehand, but he said his teammates' familiarity with him was helpful when they were talking in the dugout.

Kepler and Wallner both homered on fastballs.

It was one of the games where it felt like the Twins were always in trouble. They were outhit 11-6. The Diamondbacks stole eight bases but stranded 12 runners on base. The Twins bullpen gave up a tying double in the seventh inning and a go-ahead homer in the ninth.

"Whatever anyone is going through in here, we seem like we're really playing for another," Kepler said. "It doesn't matter. I was 0-for-3 going into the last at-bat. We're just trying to win the situations and it doesn't seem as individual as it might have in the past."

Dallas Keuchel, making his Twins debut, gave up one run in five innings in a start that was delayed more than two hours by weather. The 2015 AL Cy Young Award winner didn't record a strikeout against any of his 23 batters, but he worked ahead in counts with 18 first-pitch strikes.

With the help of timely defense, Keuchel walked a tightrope as he gave up eight hits and two walks. Third baseman Willi Castro saved two runs from scoring in the third inning when he snared a line drive that left Walker's bat at 112 miles per hour.

With a runner on first base in the fourth inning, Wallner made a sliding catch while avoiding Castro in shallow left field. Keuchel thanked Wallner for the catch in the clubhouse afterward.

"I'd like to be a little bit more crisp with two strikes," Keuchel said. "I know I got some ground balls, but at the same time, there are going to be some punchouts needed in certain situations moving forward rather than just trying to rely on a double play. But no complaints. I'm not going to sit here and be upset."

Correa, who grounded into double plays in his first two at-bats, dropped a two-run single to left field against D-Backs ace righthander Zac Gallen in the sixth inning to give the Twins their first lead at 2-1. Correa broke into a smile as he looked at his teammates in the dugout.

"We've been waiting to get on a good streak," Correa said, "and we've been playing really good baseball as of late."