KANSAS CITY -- Tanner Bibee has proven time and time again he can pitch in the biggest moments -- it’s why he’d be Cleveland’s ace for this postseason. Tuesday was no different.

The Royals loaded the bases with nobody out in the sixth trailing by two runs, but the Guardians stuck with the 25-year-old right hander to get out of the jam in this crucial AL Central matchup -- and he did just that.

Bibee kept Cleveland’s lead, allowing just one run to come home on a sac fly, to squash Kansas City’s best scoring chance of the game and lead the Guardians to a 7-1 win on Tuesday at Kauffman Stadium. Cleveland, now just a half-game behind Baltimore for the best record in the American League, moved to 4 1/2 games over Minnesota, which lost to the Rays on Tuesday, and 5 1/2 games over the Royals for first place in the division.

But the game was decided in the sixth. After a 10-pitch walk to Michael Massey loaded the bases for All-Star catcher Salvador Perez, Bibee put together his best sequence of the night. He got Perez to line out to left, shallow enough to keep the runner at third, before Paul DeJong lifted a sacrifice fly to left-center.

Bibee then sealed his quality start, and stranded the tying run on second base, with a strikeout of MJ Melendez to end the sixth. Bibee threw four straight four-seam fastballs -- his best pitch Tuesday -- to pick up his sixth and final strikeout. He generated 11 whiffs on 26 swings with that pitch.

So, what did manager Stephen Vogt learn from watching Bibee in his first September test during this playoff push?

“Just that he can make pitches in big-time moments,” Vogt said. “ … Tanner’s a big-time pitcher, and he wants those moments. For him to be able to slow down and execute in that situation was huge.”

Bibee immediately screamed and spun around when he got Melendez to strike out on a foul tip on the high heater. Against a club that has now lost seven straight games, Cleveland keeping the lead in that frame changed the entire night’s momentum.

“ … I got three consecutive outs after that. I mean, I think bases loaded, no one out, and give up one run is kind of a win,” Bibee said.

It was definitely a win for Cleveland’s rotation, which now has four straight starts of at least six innings while allowing one run or fewer for the first time this season. Guardians starters still have a combined 4.56 ERA, which ranks 24th in MLB, but to escape a jam like Bibee did in the sixth fired up the entire squad.

“That was huge,” said Kyle Manzardo, who tied a career-high with three hits. “I mean, it freed us up a little bit, but it also, I feel like, probably kicked the lineup a little bit. Said, ‘Alright, let’s go get some more runs to support this guy because he’s going to war out there for us.’”

And that’s exactly what they did. After narrowly escaping the Royals’ rally in the sixth, the Guardians put together one of their own led by Brayan Rocchio in the seventh. The 23-year-old shortstop tried to bunt over the runner on first, but instead ended up clobbering a 372-foot homer down the left-field line to give Cleveland a 4-1 lead. A sacrifice fly in the second and RBI walk in the eighth bookended his career-high four-RBI night.

“I got a pretty hard time in the dugout for that one, for putting the bunt sign on,” Vogt said while smiling. “But again, that’s just refocusing. It’s really easy when you don’t do your job or you don’t get the job done to get down on yourself and just give away an at-bat. But he got a pitch up and he crushed it.”

If the Guardians are going to make a deep run this postseason, they’re going to need outings like this from Bibee. The bullpen has been possibly historically good, José Ramírez and Josh Naylor have displayed the ability to power this lineup, but if the starting pitching can take over as well? That’s when Cleveland can get even more dangerous.

“Those guys in the bullpen have carried the load all year,” Vogt said pregame. “And so for them to get a little reprieve the last few days has been huge. Our starting pitching is capable of doing this every night. ”