SEATTLE – The Seattle Mariners are rolling out a different lineup for Game 4 of the American League Championship Series on Thursday night against the Toronto Blue Jays.

Most notably, right fielder Victor Robles is out of the lineup and utilityman Leo Rivas will make his first career postseason start. Rivas will bat ninth and play second base.

Robles has struggled this postseason, batting just 3 for 26 with two doubles. He crashed into the wall in foul territory while making a leaping catch in the third inning of Wednesday night’s Game 3, but Mariners manager Dan Wilson said during his pregame press conference Thursday that Robles is OK.

“Yeah, he’s fine,” Wilson said. “A great catch, a great effort, which is what we always see from Victor. As we talked about last night, sort of reminiscent of that play in San Francisco going in there hard, but that’s the effort you always get from Vic.”

With Robles out of the lineup, Dominic Canzone will start in right field after serving as Seattle’s designated hitter for the first three games of the series. Jorge Polanco will move from second base to DH, while J.P. Crawford will move up one spot to eighth in the batting order.

Rivas was one of the heroes of last Friday’s marathon 3-2, 15-inning win over the Detroit Tigers in Game 5 of the ALDS. Rivas delivered a pinch-hit, game-tying RBI single with two outs in the seventh inning, which was the last run by either team until Polanco’s 15th-inning walkoff single that sent the Mariners to the ALCS.

Related: ‘Best day ever’ for Mariners’ unlikely Game 5 hero Leo Rivas

Rivas is 1 for 5 with two walks this postseason. During the regular season, he batted .244 with a team-high .387 on-base percentage and a team-high 18% walk rate in 48 games.

“I think we have seen some really good at-bats from Leo throughout his time with our club – certainly the game against Detroit, picking up that huge pinch-hit knock,” Wilson said. “What he’s done at second base is stellar as well. So (we’re) getting a chance to get him in there, and I think it should work out well.

“Just his ability to grind out pitchers down at the bottom of the order is helpful,” Wilson added. “I think he identifies exactly with what he needs to do down there at the bottom of the order, and looking forward to getting that in there tonight with him.”

Here’s the Mariners’ new-look lineup for Game 4 against Blue Jays veteran right-hander Max Scherzer:

1. Randy Arozarena, LF
2. Cal Raleigh, C
3. Julio Rodríguez, CF
4. Jorge Polanco, DH
5. Josh Naylor, 1B
6. Eugenio Suárez, 3B
7. Dominic Canzone, RF
8. J.P. Crawford, SS
9. Leo Rivas, 2B

Tell a friend it’s La Piedra Day 💪 #SeizeTheMoment pic.twitter.com/PcMzNYwWsH

— Seattle Mariners (@Mariners) October 16, 2025

Veteran right-hander Luis Castillo will start on the mound for Seattle.

The 32-year-old Castillo started Game 2 of the ALDS against Detroit, working around four walks to toss 4 1/3 scoreless innings of one-hit ball. He also came out of the bullpen for the first time in his career last Friday night, retiring all four batters he faced while working the final 1 1/3 frames of the 15-inning ALDS marathon.

Jays remove Santander from ALCS roster

The Blue Jays removed outfielder Anthony Santander from their ALCS roster due to a back injury and replaced him with outfielder Joey Loperfido. Santander was scratched from Toronto’s Game 2 lineup before returning to start Game 3.

With Santander out, the Blue Jays made several changes to their lineup for Game 4. Isiah Kiner-Falefa will get his first start of the series at second base, Addison Barger will move from third base to right field and Ernie Clement will move from second base to third base.

Here’s the Blue Jays’ lineup:

1. George Springer, DH
2. Nathan Lukes, LF
3. Vladimir Guerrero Jr., 1B
4. Alejandro Kirk, C
5. Daulton Varsho, CF
6. Ernie Clement, 3B
7. Addison Barger, RF
8. Isiah Kiner-Falefa, 2B
9. Andrés Giménez, SS

Let’s keep it going! #WANTITALL pic.twitter.com/66UKmZZ2sR

— Toronto Blue Jays (@BlueJays) October 16, 2025

The 41-year-old Scherzer will be making his first start since Sept. 24, which was the final week of the regular season.

Scherzer is a three-time Cy Young Award winner and eight-time All-Star, but he’s coming off the worst season of his decorated career. After missing nearly the entire first three months of the season due to thumb inflammation, he posted a career-worst 5.19 ERA over 17 starts and was left off the Blue Jays’ ALDS roster.

First pitch for Thursday night’s Game 4 is at 5:33 p.m. Radio coverage on Seattle Sports will begin at 2 p.m. with an extended pregame show. The TV broadcast will be on FS1.

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