HARWICH, Mass. — With the roster churn that comes with being 25 games into the Cape Cod Baseball League season, Brewster Whitecaps manager Jamie Shevchik had no choice but to reach into his bullpen to find a starter for his team’s crucial matchup against the Harwich Mariners.

The 12th-year skipper selected left-hander Sebastian Santos-Olson (Miami), who made five starts (16 total appearances) during his freshman collegiate season and had 7.2 scoreless innings of relief work across six outings under his belt on the Cape.

Santos-Olson toyed with fire throughout his outing, resulting in a high pitch count that drove him out of the game early. Still, he limited damage, stranding seven baserunners across three innings while his offense did what opposing batters couldn’t: take advantage of mistakes.

Brewster’s (16-7-2) offense brought home six runs on nine hits at Whitehouse Field on Tuesday night against Harwich (15-10), and the bullpen slammed the door with six innings of one-run ball to help the Whitecaps emerge victorious, 6-2. The win, which awarded Brewster two points, adds a slight cushion to its hold on second place in the CCBL East Division after entering the matchup just a pair of points ahead of the Mariners despite owning a 2-1 head-to-head record.

“I said this last week when we beat Harwich, it was the biggest win of the year, and (now) this is the biggest win of the year,” Shevchik said. “Anytime you beat a team that’s nipping at your heels, it becomes the biggest win of the year. To date, this is probably the biggest win we’ve had this year, just to gain a little separation.”

While the Whitecaps can breathe easy now, the game could’ve gone the other direction in the early going, with Santos-Olson working in and out of jams in all of his frames.

Back-to-back strikeouts — the first of three on the evening — got him out of the first inning with runners stranded on the corners.

He allowed a singular run in the second after a double and a single, but avoided more trouble after center fielder Michael Torres was able to track down a flyball angling toward the wall off the bat of Mariners shortstop Tyler Smolinski (Kansas State), who’s four home runs put him in a three-way tie for second in the league.

In the third, his final Houdini act revolved around leaving runners on second and third, and he earned an assist from right fielder Brody DeLamielleure (Florida State), who made a diving catch to secure the final out.

“There were a lot of barrels today,” Shevchik said. “Living on the edge is something that I don’t want to do, but it seems like we’re getting pretty good at it.

“If you’re a bad team, then there’s a grand slam that follows right after that happens. If you’re a good team, you punch the next guy out, the double play bails you out. There’s a lot of things that are happening; I’m not going to call it luck yet, I just think we’re putting ourselves where we're able to make some plays to get us out of jams.”

Santos-Olson didn’t blame running into sticky situations on moving back into a starting role, saying it’s something he’s comfortable doing, and credited his defense in helping get out of them. He also believes that the experience he gained in the bullpen was vital for Tuesday.

“The high-leverage situations out of the bullpen shape a starting pitcher,” he said. “Those high-leverage situations doesn’t really bother me, when there’s runners on base, because I've been there before and I've experienced getting out of it. It's kind of come to second nature to me to get out of tough situations now.”

Santos-Olson preparing for a backup career as an escapologist allowed Brewster to jump out to an early lead, taking advantage of Harwich blunders to do so.

Whitecaps designated hitter Cash Strayer (Florida) punished Mariners right-handed starting pitcher Thomas Martin (Maine) for committing the cardinal sin of walking left fielder Blaine Brown (Tennessee) to lead off the second inning by launching his third home run of the year over the right field wall.

The blast, which exited Strayer’s bat at 100 mph, pushed his OPS over .900 after sitting at the .765 mark at the conclusion of the team’s July 9 game just five days prior. He’s gone 8-for-11 since, and the late push helped him earn an All-Star nod.

“It’s hard to say who the big leaguers are on this team, but Cash Strayer is going to be a big leaguer,” Shevchik said. “It’s a pretty swing, he just needs time. The more ABs he gets, the more comfortable he gets.”

Whitecaps second baseman Jay Abernathy (Oklahoma) tacked on another run an inning later, once again taking advantage of a mistake, but in completely different fashion.

Abernathy reached second on a single and an error, sneaking a ball past Smolinski at short that died in the shallow grass of center field, sliding safely into the bag just ahead of the throw from Micah Rienstra-Kiracofe (Kent State).

He then advanced to third on a groundout, and with the infield in, dashed home after third baseman Nate Castellon (Cal Poly) fielded a grounder and fired a throw across the diamond.

“Just knowing that I can do it (gives me confidence),” Abernathy said. “Using my speed to an advantage, and not being reckless, but trying to create as much havoc as possible.”

Brewster tacked on three more insurance runs between the sixth and the eighth innings on a bases-loaded walk and a short but effective two-out rally, more than enough with the bullpen twirling six innings of two-hit ball.

Three Whitecaps, RHP Gaines Estridge (Air Force), LHP Sam Hentges (Air Force) and RHP Otto Espinoza (Florida State), made their summer debut in the relief effort. Estridge pitched only a single frame, as he’s due to start on Thursday, but the latter two each picked up 1.2 innings.

Espinoza was the only one of the three to run into real trouble, loading the bases with one out after a pair of walks and an infield single. Luckily for Brewster, the transfer from Cal induced a 6-4-3 double play in a full count to get out of the jam.

Righties Jordan Regulski (Duke) and Jordan Martin (Arkansas) finished the job but also brought the number of relievers used to six, putting strain on the bullpen in the first of a four-game stretch to close out the first half of the season.

Entering the All-Star break with momentum could be crucial to retaining the No. 2 seed, or even hunting down the Yarmouth-Dennis Red Sox for the No. 1 spot, but it’ll be hard to do with a spent corps of relievers.

If Santos-Olson was able to go deeper into Tuesday’s affair, Shevchik would have one less thing to worry about. Now, he needs Wednesday’s starter, right-handed pitcher Charlie Willcox (Ole Miss), to sling it efficiently and effectively.

“Everything is on Charlie Willcox’s shoulders,” Shevchik said. “I need him to go, and I need him to go long. He’s got to go out there and do a great job tomorrow and get us deep in the game because we just taxed the h— out of our bullpen.”

No pressure.