The Chicago White Sox were not going to let Cubs star center fielder Pete Crow-Armstrong walk them off for a second straight night. Boos from the Cubs fans among the 40,034 fans greeted the Sox’s decision to intentionally walk Crow-Armstrong with one out in the bottom of the ninth. That choice, after Crow-Armstrong went deep again to open Tuesday’s game, ultimately set up Alex Bregman to be the Cubs’ hero. Having already come through in the seventh to tie the game on an RBI single, Bregman replicated the moment. He attacked a first-pitch fastball from Sox reliever Trevor Richards to drive in Carson Kelly — following Kelly’s double to begin the ninth — for a 4-3 walk-off victory. In his last 21 games entering Tuesday, Bregman posted a .357 average with nine doubles, six home runs, 17 RBIs and a 1.104 OPS while leading MLB in hits and extra-base hits in that span. “You love it — sometimes you’re going to fail in them, but you want them every single time, and eventually you keep putting yourself in those spots and you keep getting those opportunities, you’re going to come through,” Bregman said. “Fortunate enough to put a good swing on it today. I thought Carson did the hard part by getting into scoring position there to lead off the inning.” A 1-hour, 28-minute rain delay paused play in the middle of the eighth inning in a tied game. The Cubs (74-53) secured their major-league-leading 13th walk-off win, tying the 2015 team for their most in a season within the last 90 years. They overcame starter Kevin Gausman having to depart during the fifth inning because of cramping in his left thumb/hand. “That’s a lot, and it just kind of goes to show how special this team is, how special these guys are,” Gausman said of the walk-off wins. “They always believe in each other, and when you have that, it’s tough.” The Cubs struck first against the Sox’s lefty opener Bryan Hudson. They came into Tuesday with MLB’s best offense against lefties, and the Cubs’ top two lefty sluggers quickly added to that production as Crow-Armstrong and Michael Busch hit solo home runs off Hudson. Erick Fedde, pitching in bulk for the Sox (65-60), didn’t allow a run in 4 2/3 innings. He held the Cubs to three hits, struck out five and walked two. “I think we just had a good game plan,” Fedde said. “Did a good job of throwing inside today and tying some of the big hitters up and just kind of opened up some other stuff away and some things went my way.” Sox reliever Huascar Brazobán cleaned up Fedde’s traffic in the sixth by forcing Ian Happ to fly out to strand two runners. Brazobán ran into trouble to begin the seventh, though, after walking Miguel Amaya and Michael Conforto on nine pitches. Sox manager Will Venable called on his tough righty Grant Taylor for the top of the Cubs’ lineup, and Taylor responded by striking out Crow-Armstrong and Seiya Suzuki. Bregman, locked in since the All-Star break, came through to tie the game with his two-out, two-strike RBI single. Although Gausman’s four-seam fastball (13 called strikes) and splitter (15 whiffs) yielded some productive results, the veteran left too many hittable pitches around the plate. Three consecutive two-out singles resulted in the Sox’s first run on Drew Romo’s RBI single in the second. Gausman opened the following inning by getting ahead of Murakami, 0-2, but followed with three straight balls and the Sox’s slugger unloaded on a low fastball. Murakami’s hit was 111.1 mph the opposite way off the left-center field videoboard for a game-tying 406-foot home run. “I thought we battled and got out of some tough spots,” Gausman said, “but not necessarily as sharp as I would have liked to have been.” The Sox got to Gausman again in the fourth, thanks to Tristan Peters’ RBI double. “Tough finish, but again just really proud of the guys for continuing to battle there,” Venable said. “Again, two homers in the first inning and behind the eight ball to start and our guys just never stopped battling. I thought Fedde was amazing today, what he did, especially with where we’re at, to be able to get that coverage and perform like he did was just awesome. He gave us a chance to win that game. Tough result again, but just a really good job by the guys.” Gausman’s hand cramp initially popped up during the fourth when his left thumb became locked in an awkward position, prompting a mound visit from Counsell and head trainer Nick Frangella. After several minutes, Gausman threw a few pitches and stayed in the game. He struck out Sam Antonacci to end the inning and returned for the fifth. However, Gausman only made it through two Sox hitters — striking out Murakami and allowing a single to Miguel Vargas — before the cramp again bothered him to the point of exiting the game following a brief conversation with Counsell and Frangella. “My thumb, kind of couldn’t even put it in my glove there in the fourth before I got some electrolytes in me, and felt fine to start the next inning,” Gausman explained. “First pitch to Murakami I felt it, and then the last pitch to Vargas it kind of locked up on me again. “Pretty frustrating to be honest,” he said. “First start here as a Cub. Obviously, not what I’m trying to do. Only the second time I think in my career that I’ve left the game but just felt like I couldn’t keep going, kind of couldn’t grab my glove without it locking up on me.” Gausman said he’s experienced the cramping before, though it typically doesn’t occur until he gets over 100 pitches; he came out of the game at 86 pitches. He credited right-hander Javier Assad for coming in and saving the day. Assad got the unexpected appearance in relief of Gausman and gave the Cubs exactly what they needed. He tossed three shutout innings while allowing two hits, no walks and striking out two. It continued an excellent stretch by the 29-year-old, who keeps stepping up in whatever role he’s given. “Javy put the game back in order for us,” Counsell said. Since May 1, Assad has a 2.24 ERA in 64 1/3 innings that span 10 relief appearances, two saves, seven starts and five games finished.