The Boston Red Sox will look to extend their season-high winning streak when they play the third contest of a four-game series against the visiting Seattle Mariners on Saturday afternoon.

Boston goes for four straight wins after the long ball carried the offense again on Friday. Trevor Story's grand slam and Jackie Bradley Jr.'s three-run home run provided all the offense in a 7-3 win over Seattle.

"I think guys are just staying consistent with their work," Bradley told NESN after the game. "We're not focused on the standings right now, just a game at a time."

Story continued his dynamic week, as he has four homers in the series and 22 RBIs in 17 games this month.

After beginning the season in relief, Boston's Garrett Whitlock (1-1, 2.43 ERA) is slated to make his sixth start of the season, and his career, on Saturday.

Whitlock has allowed three runs or fewer in each outing this season, though he has yet to log a win as a starter after getting a third straight no-decision on Monday in the Red Sox's 6-3 win over the Houston Astros.

With Whitlock being treated as a full-fledged starter, Tanner Houck has served in a piggyback role behind Rich Hill. Houck is covering multiple innings as Whitlock did late last season.

"We feel very confident where we're at right now with him. ... We believe that this is going to work," Red Sox manager Alex Cora said recently of Whitlock. "I do believe we're very close to having the structure that we want and then from there, we roll."

Boston starters have allowed two runs or fewer in 19 of the past 27 games.

Whitlock, who has yet to start a game against Seattle, pitched 2 1/3 scoreless innings of relief in a 6-5 Red Sox win over the Mariners on April 23, 2021.

Boston shortstop Xander Bogaerts collided with left fielder Alex Verdugo on a shallow fly ball late in the Friday game, and Bogaerts was subsequently lifted for a pinch hitter.

Cora confirmed that Bogaerts is day-to-day due to lower back discomfort on the left side.

Seattle will turn to Chris Flexen (1-6, 4.35), who has lost four consecutive starts since an April 22 win over the Kansas City Royals. He fell to the Toronto Blue Jays on Monday despite striking out seven, as he allowed three runs on six hits over 5 1/3 innings.

Flexen has yielded three or fewer runs in all but one of his seven starts -- a May 9 setback to the Philadelphia Phillies in which he allowed six runs over five frames.

A major reason for his win-loss struggles is being supported with just 1.14 runs on average, the lowest in MLB among pitchers who have made more than two starts.

"For me, you're out there trying to compete, put us in the best situation to win a ballgame," Flexen said. "(The offense continues) to battle, as we saw with a late little rally at the end there (at Toronto on Monday). It's part of the game. I'm going to go out there and continue to try to compete and execute."

Seattle has been limited to three or fewer runs in three of the past five games.

Flexen's only previous start against Boston came on April 24, 2021, when he held the Red Sox to a single run on four hits with seven strikeouts over seven innings in an 8-2 win.

Before the Friday game, Seattle reliever Matt Festa returned from the injured list after missing two weeks due to a sore elbow. Reliever Wyatt Mills was returned to Triple-A Tacoma.

"Matt was off to a really good start," Mariners manager Scott Servais said. "We've used him in different roles. We'll ease him back in. We should be in pretty good shape with the bullpen."