CHICAGO -- Jason Heyward was out of the starting lineup for the Cubs for the past two games. Manager David Ross constructed his orders with the platoon advantage in mind, rendering the veteran outfielder to pinch-hit duties.

"It's a new situation, but it's a part of it," Heyward said. "To get where we want to be as a team, you're going to have to do things you're not always called on to do."

In the 10th inning of Thursday night's 4-3 win over the Mets, Heyward was called upon to face closer Edwin Díaz with the bases loaded. It was precisely the kind of matchup Ross had in mind, and why the manager kept Heyward waiting for the first nine frames. Ross liked Heyward’s approach against the closer’s high-octane arsenal.

Heyward answered the call by pulling a 98-mph fastball from Díaz through the infield and into right field for a walk-off single. The celebratory mob scene was on, following Chicago's first series sweep and walk-off victory of the year.

And it was a win that nearly slipped out of Chicago's grasp at multiple turns.

"That's a good character win right there," Ross said. "Things weren't playing out the way I think we wanted, and felt like we didn't come through in some moments, but you know what? Guys stepped up, made pitches when they had to, made plays.

"And we come through with the big knock there at the end with J-Hey. Things worked out for us in the end."

One of those near-costly moments arrived in the seventh inning, when Javier Báez led off by lofting a pitch from Trevor May to shallow right-center. Báez appeared frustrated as he headed slowly out of the box -- before the ball dropped between outfielders Michael Conforto and Kevin Pillar.

Not only could Báez potentially have made it to second on the play, but the shortstop was also nearly thrown out on his retreat to first. Matt Duffy followed with a double play and David Bote struck out, keeping the contest in a 3-3 deadlock.

"I talked to Javy about that," Ross said succinctly. "We discussed it."

Enough said.

Then, Jake Marisnick led off the eighth inning by sending an Aaron Loup pitch up the right-field line. The Cubs center fielder sprinted around the bases, sliding into third with a triple. He clapped his hands hard and yelled at Chicago’s dugout. That is where Marisnick remained, as the next three hitters were retired in order.

In the ninth, the Cubs had another opportunity to pull ahead when Kris Bryant -- already with a two-run double earlier in the night -- opened with a single. Following strikeouts by Anthony Rizzo and Báez, Bryant attempted to steal second with Duffy batting.

"He looked safe to me. I thought he got in there," Ross said.

Indeed, Bryant slid in ahead of the throw from catcher James McCann, but second baseman Jeff McNeil held the tag on as the play progressed. Bryant was deemed out and there was the briefest of moments when his feet looked like they may have left contact with the base.

The Cubs challenged, but the out call was upheld, ending the inning.

"I thought it was a nice jump. I thought he had the bag," Ross said, "whether he popped up for a millisecond or not. We've seen some of the things come in with replay that are probably not the reason why we brought in replay.

"Whatever. We won the game. I'm happy."

That's right. The Cubs dodged all those potential pitfalls and finished off a three-game brooming that pulled the club's record up to 9-9 on the campaign.

"For us to get our first sweep," Cubs starter Trevor Williams said, "I think it was really a step forward for us to put behind the previous three weeks or two weeks of the season. And we're starting to ride that flow."

The Cubs held on for a close win in the opener. They routed the Mets, 16-4, in a wild game on Wednesday night. And then in the finale, following a series of setbacks, Chicago found a way to the win column again, and with the rival Brewers coming in next.

"Sometimes you don't execute everything you want to in a game," Ross said. "But, you come away with a win and you feel really good, especially after a grinder like that."