Riley O'Brien realized a dream in 2022 when he made one appearance for his hometown Seattle Mariners.

He returned to the city this week as a major league closer.

O'Brien didn't get a chance to pitch Monday as his St. Louis Cardinals lost 4-2 to Seattle, but he might get an opportunity Tuesday night when the three-game interleague series continues.

"It's definitely weird to think about, but I'm excited to go back and hopefully throw some meaningful innings there," said O'Brien, who attended Shorewood High in the suburb of Shoreline, just north of Seattle. "(Sticking in the big leagues) is a really good feeling. I've still been in the day-to-day grind mode and haven't really reflected on this year yet, but I'm sure in the offseason I'll be proud of this year."

It's been a long road for O'Brien, 30, who spent all or parts of eight seasons in the minor leagues -- with four different organizations -- and was optioned to Triple-A Memphis three times earlier this season. He got his big break when the Cardinals dealt closer Ryan Helsley and set-up men Steven Matz and Phil Maton at the trade deadline in July.

O'Brien earned a win and a save over the weekend against the San Francisco Giants.

"Once we got to the deadline and we lost those three guys, each one of the other guys bumped up into a more significant role," Cardinals manager Oliver Marmol said. "(O'Brien) has taken to the (closer's role) well. A big part of it for him is staying healthy, and he's done a nice job of that.

"He's stayed on the attack and hasn't given in regardless of what happens. He hasn't allowed a negative to impact the next pitch, and that's probably the biggest difference for him. Just the overall self-talk and staying locked in regardless of the circumstance has been big for him."

O'Brien said he expected about 40 family members and friends in attendance at T-Mobile Park. Missing will be grandfather Johnny, a former multi-sport standout at Seattle University and major-leaguer who died June 13 at age 94.

"I was always going there as a kid and watching Ichiro (Suzuki) and I had the dream of playing there, but it never seemed realistic," said O'Brien, who actually realized his dream of pitching for the Mariners when he threw one inning on May 7, 2022, giving up no runs and one hit against visiting Tampa Bay.

On Monday, the Cardinals (72-73) took a lead on Alec Burleson's two-run homer in the fourth inning, but the Mariners (76-68) rallied with four runs in the sixth. Josh Naylor's two-run double with the bases loaded gave Seattle the lead, and he proceeded to steal third and score an insurance run on Jorge Polanco's sacrifice fly.

"He's just a smart player, and we've talked about how he's able to find little advantages that he can get and then he takes advantage of them," Mariners manager Dan Wilson said of Naylor.

The victory was the third in a row for the Mariners, who pulled within two games of Houston in the American League West race and remained 1 1/2 games ahead of the Texas Rangers for the AL's third and final wild-card berth.

Tuesday's pitching matchup is scheduled to feature a pair of former first-round draft picks in Cardinals left-hander Matthew Liberatore (7-11, 4.15 ERA) and Mariners right-hander George Kirby (8-7, 4.47).

Liberatore had lost five straight decisions since a June 29 win before pitching 5 1/3 scoreless innings to beat the visiting Athletics 5-1 last Wednesday. Liberatore allowed four hits, walked one and struck out seven. He's 0-0 with a 27.00 ERA in one previous relief appearance against Seattle.

Kirby is coming off the shortest start of his career, lasting just two innings in a 9-4 loss Wednesday at the Tampa Bay Rays. Kirby gave up eight runs (seven earned) on 10 hits. He's never before faced the Cardinals.