The Orioles avoided salary arbitration with one of their highest-profile players, announcing they agreed to a one-year deal with Trey Mancini ahead of Friday’s deadline. Mancini's signing left Anthony Santander as Baltimore's lone arb-eligible player unsigned as of Friday’s deadline.

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Mancini’s contract is worth $4.75 million, a source told MLB.com's Mark Feinsand, while Santander is seeking a significant raise as a first-year arbitration-eligible player. Unless the Orioles and Santander can reach an agreement in the coming weeks, a hearing to determine Santander’s 2021 salary would be set for February. The last time the O’s went to trial was with reliever Brad Brach in '17.

It was once common for teams and players to continue negotiating contracts until the day of their arbitration hearings, but that practice has become less frequent in recent years. Still, it’s a relatively uncommon situation for the O’s to find themselves in; they’ve gone to trial just 13 times since Peter Angelos became the majority owner in 1993, winning 11 of those cases.

Feinsand reported that Santander filed for a $2.475 million salary for 2021, while the Orioles countered with $2.1 million, leaving a gap of $375,000. That gulf stems from the disjointed nature of Santander’s breakout 2020 season. Emerging as the undisputed everyday right fielder and a player to build around, Santander broke out to hit .261 with 11 home runs, 32 RBIs and an .890 OPS in 37 games, before a left oblique injury ended his season.

With Mancini absent due to health reasons, Santander flourished as the O’s everyday No. 2 hitter before his injury ended his season prematurely. If there were a 2020 All-Star Game, Santander would’ve been the O’s slam-dunk candidate. But how does that translate salary-wise, given just an unusually small sample?

That is a question an arbitration panel might well decide. Whatever the final figure, it will be significantly more than the roughly $550,000 Santander earned in 2020.

Mancini made the same salary on a prorated basis last season, which he missed entirely to undergo treatment for Stage 3 colon cancer. He completed chemotherapy treatment in September and resumed baseball activity, including batting practice, by mid-October. Both Mancini and Orioles general manager/executive vice president Mike Elias have expressed confidence that Mancini will be healthy enough to return to the field by Spring Training.

“He’s almost at the finish line and I can’t wait to see him hit in Sarasota,” Elias said in December.

The diagnosis came on the heels of a breakout 2019 season for Mancini, who hit .291/.364/.535 with 35 home runs and 97 RBIs in his age-27 season. It was production that rendered Mancini the new face of the rebuilding Orioles, as well as their top potential trade chip and extension candidate. Mancini projects to play predominantly first base as he returns to the middle of an improving lineup of young players, including Santander and Ryan Mountcastle.

Santander and Mancini were two of the Orioles' eight arbitration-eligible players at the beginning of the offseason. The team already agreed to deals with infielders Yolmer Sánchez and Pat Valaika, catcher Pedro Severino and reliever Shawn Armstrong. The O's released Renato Núñez and non-tendered Hanser Alberto late last year in related moves.