PEORIA, Ariz. -- The Mariners signed veteran reliever Sergio Romo to a one-year contract, the club announced Thursday.

Per sources, the agreement is for $2 million with a $250,000 trade assignment bonus. The club's 40-man roster is now at 39 players.

“Sergio’s stuff and style bring a unique look to our bullpen,” Mariners president of baseball operations Jerry Dipoto said. “He is incredibly competitive and has shown the ability to rise up in big moments throughout his long Major League career. He is a solid fit for us.”

Romo, 39, is expected to fill the void left by Casey Sadler, who will undergo season-ending shoulder surgery in the coming days. As such, Romo will likely see most of his playing time in the “pivot” role, as Mariners manager Scott Servais described, the spot between the starter and the rest of the bullpen. Other in-house arms will be candidates for the gig, too.

Because the Mariners will deploy their relievers in the most favorable matchups, Romo could be used in other pockets as well. Sans Sadler, Seattle is returning nearly all of its bullpen from last year, which ranked fourth in the Majors with 7.0 wins above replacement, per FanGraphs. And that group is adding what it believes will be two high-caliber arms coming back from injuries, Ken Giles and Andrés Muñoz.

A one-time All-Star who has spent 14 seasons in the Majors, Romo spent last year with Oakland, for which he compiled a 4.67 ERA and 88 ERA+ (league average is 100), with a a 23.2% strikeout rate and an 8.1% walk rate, all of which represented a downturn from his best days. Yet his 37.5% ground-ball rate and 84.9 mph average exit velocity against, which ranked in the 98th percentile, per Statcast, paint a clearer picture as to what the Mariners value in the veteran.

The soft-tossing sidearmer also has a long track record of success against righties, with an opposing slash line of .201/.245/.347 (.593 OPS) for his career, and his career 77% strand rate makes him an ideal fit for the pivot role. Romo was in line to pitch for Acereros de Monclova in the Mexican League before the deal with the Mariners manifested.

His agreement brings the projected 40-man payroll to roughly $117 million, per Cots Baseball Contracts, though the club still has cases to settle with Mitch Haniger, Adam Frazier and Jesse Winker, who were the only arbitration-eligible players who did not reach an agreement on salary ahead of Tuesday’s deadline to exchange figures. The separation between all three is a little more than $4 million total.