Red Sox place Mickey Gasper and Tyron Guerrero on IL ahead of Wild Card Series vs. Yankees

The Red Sox head into their Wild Card Series against the Yankees missing two of their more useful contributors, after the club announced a wave of roster moves ahead of Sunday's season finale against the Cubs.

What happened

Per MLB Trade Rumors' Charlie Wright, Boston placed catcher Mickey Gasper on the 10-day injured list with a biceps strain and right-hander Tyron Guerrero on the 15-day injured list with what was later identified, per the Boston Globe's Tim Healey, as a Grade 2 lat strain. To fill the vacated roster spots, the club recalled utilityman Nate Eaton and right-hander Wyatt Olds.

The club also activated right-hander Tanner Houck from the 60-day injured list. Houck, who had Tommy John surgery last season, is starting Sunday's finale in what is his return to the majors. To clear a 40-man spot for Houck, outfielder Eli White — who had season-ending foot surgery earlier this month — was moved to the 60-day injured list. Jedixson Paez was optioned to create room on the active roster.

Sunday's game is being played at Tropicana Field rather than Boston, relocated there due to weather conditions.

Why it matters

Gasper's absence stings in a specific, lineup-construction kind of way. Manager Chad Tracy called the biceps injury "significant" after Gasper was removed from the first game of Friday's doubleheader, and per Charlie Wright at MLB Trade Rumors, he is expected to miss at least the first round of the playoffs. His full postseason availability is in doubt. Gasper had settled into a regular role against right-handed pitching near the top of Boston's lineup, and the DH spot he occupied won't be as straightforwardly filled heading into October.

There is, however, a notable offset. Willson Contreras is hitting third as the designated hitter Sunday — his first appearance since September 17, per the report. Contreras had been dealing with hand pain after being hit by a pitch, and his presence in the lineup is described as a positive sign for his postseason availability. Whether that availability holds remains to be seen, but the optics of him taking at-bats in Game 162 are at least encouraging for a club that needed some good news on the position-player front.

Guerrero's situation carries a different kind of weight. The Grade 2 lat strain is the more serious of the two diagnoses, and per Tim Healey of the Boston Globe, such injuries typically require at least a month of recovery. That timeline puts his entire postseason in jeopardy. Per Charlie Wright at MLB Trade Rumors, advancing multiple rounds would likely be a prerequisite for Guerrero to have any realistic chance of returning — a scenario that is, by definition, not guaranteed.

That matters because Guerrero had carved out a meaningful role in the bullpen. He was functioning as a key setup option behind Garrett Whitlock and Aroldis Chapman, and he earned his 19th hold in his most recent appearance — a strikeout-the-side outing against the Guardians on Wednesday. Losing a reliever who had that kind of late-inning trust, right before a playoff series, is the sort of thing that quietly reshapes a manager's options in ways that don't show up in a box score until they do.

The numbers

Boston enters the postseason at 87-75 (.537), sitting third in the AL East and 11 games back in the division race — which they have been eliminated from. Their Wild Card standing is rank 2, sitting +3.0 relative to the cut line.

Nate Eaton, recalled as part of the roster shuffle, has compiled 58 plate appearances across his various stints with the club this season, per MLB Trade Rumors. He brings big-league experience at third base, though he has played only the outfield with Boston this year. Per the report, he has put up 4 Defensive Runs Saved in the field this season.

Where the club stands

Boston carries an 87-75 record into the postseason, having clinched their playoff seeding and a Wild Card Series matchup with the Yankees — a series set in the days leading up to Sunday's finale. The Red Sox enter on a one-game losing streak.

The Wild Card Series opens Tuesday, September 29 at Yankee Stadium, where Boston's probable starter is listed as TBD against Cam Schlittler. Wednesday, September 30 has Boston facing Max Fried, and Thursday, October 1 would see Gerrit Cole on the mound for New York if the series extends that far — with Boston's starters again listed as TBD across both games.

The rotation picture is its own open question. Houck's activation and Sunday start is the most concrete piece of pitching news the club has offered heading into October, and even that comes with the caveat that he is returning from Tommy John surgery. The bullpen, meanwhile, is now navigating without Guerrero, whose 19 holds this season reflected a level of late-inning trust that won't be easy to redistribute on short notice.

What we don't know yet

Guerrero's postseason status is the most pressing uncertainty. Per Tim Healey of the Boston Globe, the Grade 2 lat strain typically requires at least a month of recovery, which puts his availability for any part of the postseason in serious doubt. Per MLB Trade Rumors, the path back would require Boston to advance deep into October — a scenario that remains very much unresolved.

Gasper's situation is somewhat clearer in its immediate contours — he is expected to miss at least the first round per the report — but whether he could return later in a deeper postseason run is not addressed.

Contreras' status is the most optimistic unknown. His appearance Sunday is described as a good sign for his postseason availability, but MLB Trade Rumors stops short of calling it a certainty. He was still feeling hand pain earlier this week after being hit by a pitch, and one game of DH work in the regular season finale is not the same as a clean bill of health.

What to watch

The most immediate question is how Boston constructs its Wild Card roster without Guerrero in the bullpen. The setup roles behind Whitlock and Chapman will need to be redistributed, and the club's decisions about which arms make the postseason roster — and in what order they're deployed — will be worth tracking before Tuesday's first pitch at Yankee Stadium.

Contreras' health between now and Tuesday is the other thread to follow. If he is available and functional at DH, it softens the blow of Gasper's absence meaningfully. If the hand remains an issue, Boston's lineup construction against New York gets more complicated in a hurry.

And then there is Houck, who is starting Sunday in his first major-league appearance since Tommy John surgery. How he looks — and how the club characterizes his role going forward — will be one of the more closely watched storylines of the day, even if the game itself is a season finale being played at a neutral site due to weather.

The Yankees series starts Tuesday. The roster, as of Sunday, is still being assembled.