The Detroit Tigers entered Friday — the deadline to exchange salary numbers — with five arbitration-eligible players unsigned.

But by the end of the night, all but one — Michael Fulmer — were inked to deals. No contract handed out Friday was bigger than the trickiest one, Nicholas Castellanos.

According to multiple persons with knowledge of the situation, right fielder Nicholas Castellanos — whose salary calculation was considered difficult given the disparity between his offensive and defensive performance in 2018 — signed a one-year deal for $9.95 million. The Tigers later confirmed the move.

Castellanos had been projected to receive $11.3 million in arbitration, according to mlbtraderumors.com, accepted as an industry source.

[Tigers will trade Nicholas Castellanos. But when? ]

He is coming off a career-best season offensively — hitting .298 with 23 home runs, 46 doubles and 89 RBIs in 2018 — but the former third baseman also ranked as one of baseball's worst defensive outfielders in baseball. The Tigers avoided arbitration with Castellanos last winter with a one-year, $6.05 million deal.

A free agent after the 2019 season, Castellanos is on the trading block, but with free agents and other trade candidates flooding the outfield market, the Tigers have yet to find teams a willing partner to part with a good prospect. A big arbitration award for Castellanos would make him even less appealing as an offseason trade target, though another solid season at the plate in Detroit could boost the demand for him at the trade deadline, assuming the Tigers are once again far from contention.

On Thursday night and Friday afternoon, the Tigers reached deals with four other players. Closer Shane Greene signed for $4 million, lefties Matt Boyd and Daniel Norris signed for $2.6 million and $1.275 million, respectively, and lefty Blaine Hardy signed for an undisclosed amount.

[Tigers prospect Gregory Soto suspended 20 games by MLB ]

Fulmer is the only arbitration-eligible Tiger yet to sign.

Though it is unclear how the team and Fulmer’s representatives will proceed in negotiations, there is a strong chance that the two sides are far enough apart that an arbitration hearing is necessary.

The right-hander is projected to earn $3 million in arbitration, according to mlbtraderumors.com.

The Tigers have not had a player’s salary determined by an arbitration panel since 2001, before general manager Al Avila joined the organization. Their stance, while not set in stone, has been to avoid the potentially awkward hearings at all costs.

While the deadline for exchanging salary figures is Friday, the hearings won't begin until Jan. 28 (with a final date of Feb. 15). Teams and players are allowed to continue negotiations until the hearing, after which the arbitrator will issue a decision about which salary figure best reflects the player's value. (Arbitrators are only allowed to pick one number or the other; they cannot pick a figure in between the two.)

[ Detroit Tigers mailbag: Have we seen rock bottom yet in rebuild? ]

Contact Anthony Fenech: afenech@freepress.com. Follow him on Twitter @anthonyfenech.

Download our Tigers Xtra app for free on Apple and Android devices!