SEATTLE -- Nick Margevicius saved his best for last and, in the process, kept the Mariners at least mathematically alive in the postseason hunt with four games remaining.

The 24-year-old southpaw threw six scoreless innings on Wednesday as Seattle topped the Astros, 3-2, in the Mariners' final home game of the year at T-Mobile Park. With a 25-31 record, the Mariners head to Oakland needing to sweep the American League West-leading A's and have the 28-28 Astros drop four straight to the last-place Rangers to claim the AL West's No. 2 playoff spot. Houston owns the tiebreaker over Seattle by virtue of a 7-3 head-to-head record.

• Box score

The Mariners have a similarly faint heartbeat remaining in the AL Wild Card chase, where the Blue Jays hold the No. 8 playoff seed at 29-27 after beating the Yankees, 14-1. Seattle owns the tiebreaker over Toronto should both clubs finish with an identical record, but the Mariners again would need to sweep the A's and have the Blue Jays lose their final four games of the season.

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"We're still playing for something," said designated hitter Ty France, who went 2-for-4 with a double and two RBIs. "We still have a little bit of a chance and we know that. We're coming out with some fire and just running with it right now. It's a good group of guys, a lot of young guys, and we like to have fun."

One of the youngsters is Margevicius, who moved into the rotation in early August to replace the injured Kendall Graveman. The lanky lefty allowed just three hits and closed out his year at 2-3 with a 4.57 ERA. The six innings equaled the longest start of his career.

Margevicius' fastball velocity was down a tick as he averaged 89 mph, per Statcast, but he leaned more on his 70 mph curve and an 82 mph changeup to keep the Astros off-balance.

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"Marg really hung in and executed well," said manager Scott Servais. "You look at his final line and the results were outstanding. He'd probably be the first to tell you maybe it wasn't the best stuff he's had, as far as crispness. But he's learning. He's learning the value of that curveball."

Margevicius came into the season competing for a long spot in the bullpen after being claimed off waivers from the Padres, who rushed him to the Majors at age 22 and then designated him for assignment after a rough rookie season. But he's found a home in Seattle and could be part of the youthful rotation going forward.

"Sometimes you need a little luck involved and he landed in the right place," Servais said. "He landed in a Mariners uniform, and it is the year of opportunity with our young players. I think he's very grateful for that. We're super grateful.

"I love having him out there, love how he competes. He's only going to get better. Left-handed, you throw strikes and you're coming up with some other pitches and really have some guts and heart to you -- you're going to win a lot of games in this league."

Margevicius said ending his season on such a positive note will only further motivate him through the winter workouts and a chance to keep building on his opportunity. His lesson in this crazy year is to be ready for anything after being let go by the Padres.

"I don't know exactly how I got up [to the Majors] so soon or why I was DFA'd so young, but I feel I'm in a good place now," Margevicius said. "Especially with the Mariners and what they're doing with me developmentally and progressing me forward, I'm really encouraged and excited for what the future holds. I got lucky. I ended up in a good spot and I feel good about it."

The Mariners had gone 2-24 against Houston over the past two years before winning two-of-three for their first series win over the Astros since 2018 and their first home series victory against Houston since 2016. After getting off to a 2-7 start, the Mariners finished their home season with a 14-10 record.

"It has really been hard without our fans in the stands," Servais said. "I can't give our players enough credit, but I want the fans to understand how much they have missed them. It has been a challenge. Let's all keep our fingers crossed that we can put the fans back in the stands next year because we have really missed them."