PEORIA, Ariz. -- Kyle Seager has been the most durable third baseman in the Majors for the past seven years, but that iron-man status hit a bump on Monday as the Mariners announced the 31-year-old was to have surgery to repair a tendon in his left hand on Tuesday and will miss at least the first month of the season.

Seager hurt his hand diving for a ball down the line on Friday night against the Cubs.

Seager has never missed more than eight games in a season since becoming Seattle’s full-time starter at the hot corner in 2012, playing in 1,079 of the Mariners’ 1,134 games at the position. Evan Longoria is second in games played by a third baseman in that span, with 917.

“This will be the first time for me having to go on the DL and that’s something I was proud of,” Seager said. “It sucks. Anytime you don’t get to go out there with your teammates and your guys, it’s hard.”

Both Seager and manager Scott Servais declined to put a firm timeline on Seager's recovery, but Servais said his third baseman will miss at least the month of April. The Mariners open their season with two games in Japan against the A’s on March 20-21.

“I think a lot of it will depend on the rehab part of it, how quickly I can get through that type of stuff,” Seager said. “[The doctor] really didn’t give too definitive a timeline, but I think it’s going to be a little while. I won’t be in Japan, let’s put it that way.”

The injury comes at a tough time for the North Carolina native, who spent the offseason working on his flexibility and workout routine as he looked to rebound from the worst season of his career, having hit .221/.273/.400 with 22 homers and 78 RBIs in 155 games in 2018.

Seager batted .318 (7-for-22) with two doubles in nine Cactus League games this spring.

“This is our job. This is part of it, unfortunately,” Seager said. “It is what it is. I did have a successful winter, and that doesn’t necessarily take away from that. There’s still things that you can continue to work on when I’m doing this. It’s not something I really wanted to happen, but we’ll deal with it and we’ll rehab and get through it.”

With Seager sidelined, Servais will primarily turn to first baseman Ryon Healy to fill the void. Healy came up in the Minors as a third baseman and was back at that spot the past two days. He started 103 games at third with the A’s in 2016-17 before transitioning full time to first base when acquired by the Mariners last year.

But Healy didn’t even have a third baseman’s glove any more after switching glove companies, so he’s borrowing one of Seager’s for now.

“The first couple days have been fine,” Healy said. “It’s just getting my arm slot and throwing across the diamond again. But having [new infield coach] Perry Hill here is a big help, so I’ll take advantage of that as much as I can.”

Healy said the biggest adjustment is knowing when and where the third baseman shifts in different situations now. He’ll line up at essentially the second-base spot against some lefties. But he knows replacing Seager will take a team effort.

“Obviously that’s a big leader on the team that we’re losing, but the season doesn’t stop,” Healy said. “We’ve got to keep going and we’ve got to compete.”

Whoever wins the utility battle between Kristopher Negron and Dylan Moore can also play third base, and veteran free-agent signee Tim Beckham has started 45 games there in his Major League career, though he’s expected to open the season as the club’s starting shortstop.

But not having Seager’s familiar presence at the hot corner definitely will be a blow for a team that has already undergone a tremendous amount of turnover this past offseason.

“The thing you take for granted is writing guys' names in the lineup every day,” Servais said. “But life goes on. Baseball goes on. The league is not going to stop and wait for Kyle Seager to get healthy, so we keep playing and try to figure it out and get somebody else in there. It may create an opportunity for somebody else to really step up and take it and run with it.

“But it is disheartening. It’s tough when you figure he’s your everyday guy and you fire him in there for 140-150 games. It won’t be quite as many this year.”

Second baseman Shed Long, the Mariners’ No. 12-ranked prospect after being acquired this offseason, was an early hitting standout in camp and has started four Cactus League games at third base as the club looks to increase his versatility. But Long has never played above the Double-A level and was among the group of players cut from Major League camp on Monday.

Seager, a 2014 All-Star and American League Gold Glove Award winner, has the fourth-most doubles in Mariners history (249), ranks fifth in home runs (175) and extra-base hits (436), sixth in hits (1,124) and seventh in RBIs (603).