BOSTON -- With two outs in the 9th inning and the bases loaded, Pablo Reyes squared up for a bunt against Royals reliever Carlos Hernández. Fortunately for the Red Sox, he didn’t connect.

Reyes sent the next pitch, a 98.2 mph fastball, off the foul pole in left to record his first career walk-off homer and give the Red Sox a 6-2 win over the Royals in Monday’s series opener at Fenway Park.

“It was a big one,” manager Alex Cora said. “Let’s see where it takes us, but sometimes games like that kind of get you going, and we needed to get going. Even here today was kind of like, ‘Eh,’ until the end. We had a tough weekend, we were coming from a tough week and this is a great way to start the week.”

Coming off a sweep by the Blue Jays that put the Red Sox five games out of an AL Wild Card spot entering Monday's game against Kansas City, the club finally got its big hit to snap a four-game losing skid. The big hit came after a two-out check-swing call on Luis Urías that led to Kansas City manager Matt Quatraro getting ejected.

“It’s a tough job. I’m not an umpire, so I’ll leave it at that,” Cora said. “But it’s a tough job.”

The Red Sox won just hours after it was announced that shortstop Trevor Story would make his season debut in Tuesday’s game against Kansas City. Reyes, who was activated from the injured list two weeks ago, made his 15th start at shortstop on Monday. The Red Sox have not yet announced a corresponding roster move for Story’s return, but Reyes made a good case to stay on the roster.

Reyes opened his night with a single in the 3rd, before stealing second base, advancing to third on an error and scoring on a Masataka Yoshida sac fly. In the 5th, Connor Wong drove in Reyes on an RBI double for the second run of the game. Reyes tied career highs with four RBIs (also May 17 against Seattle) and four runs (June 19 at Minnesota).

“He’s a good kid and there’s a reason he’s here,” Cora said. “We like his versatility, we like his at-bats against lefties. You saw it yesterday, controlling the zone against righties. He’s a good player, he is a really good player and a good kid. … It was a great game for Pablo, I’m very proud of him.”

Starter Brayan Bello went 6 2/3 innings, marking the 10th time in his past 11 starts the right-hander has gone at least six innings. Josh Winckowski allowed Bello’s runner to score and gave up the tying run on a Bobby Witt Jr. RBI double before recording the final out of the 7th. Chris Martin and Kenley Jansen each pitched 1-2-3 innings to set Reyes up for the walk-off.

The three relievers combined for 39 pitches on the night, giving a heavily taxed bullpen a much-needed break as the Red Sox navigate a stretch of 26 games with only one scheduled off-day.

“He didn’t get frustrated, he went in there with the fastball and the last one it was up but it cut, so the guy got to it,” Cora said of Bello. “But overall [it was] what we needed, a deep outing, a good one, and he gave us a chance to win.”

It marked the second time one of Bello’s teammates has made good on their promise to the 24-year-old to homer, after Rafael Devers followed through on the prediction he made to Bello that he would hit two home runs in his first game after the All-Star break.

“My teammates were asking me, ‘Pablo, when are you gonna hit a homer?’ I said, ‘I’m going to try this week.' … When they give me the opportunity, I’m going to go up there and I’m going to try,’” Reyes said through translator Carlos Villoria. “So I started good with the two base hits, and then I said, ‘Well, I got to try to go for the big swing,’ and it happened.”

Said Bello through Villoria: “I’m very happy for him, it’s obviously a very important hit for us. He’s been telling me that he was going to hit a home run the whole week. So I’m glad that it happened today to win the game.”