Sources told Jeff Passan that the SeattleMariners are close to a deal for Luis Castillo of the Cincinnati Reds.

Sources said that minor leaguers Noelvi Marte, Levi Stoudt and Dylan Moore are going to Cincinnati.

The Mariners entered Friday's action 11 games behind the first-place Astros in the American League West and holding onto the second wild-card spot.

Ahead of Tuesday's trade deadline, they're set to add the best available arm, one that would join an already-solid rotation that also includesRobbie Ray andLogan Gilbert.

The longest active streak among the four major North American pro sports leagues is by the Mariners, who haven't made the playoffs in over a decade.

Castillo is 4-4 with a 2.86 earned run average in 14 starts for the Reds this year and has a 3.62 earned run average in six seasons with Cincinnati.

Castillo won't be a free agent until after the 2023 season, so the Mariners will have him for at least the rest of this year and all of next.

His changeup has been his best pitch for most of his career, but this year he is throwing his four-seamer more, and doing so with a lot of success. Castillo's opponents have whiffed on 39% of their swings against his four-seamer, the highest rate of Castillo's career and the highest of any pitcher in the majors.

In four starts against the American League this year, Castillo has a 1.38 earned run average, which is second to the Los Angeles Dodgers 'Clayton Kershaw who has a 0.79 earned run average.

Veteran players have been moved by the Reds since the end of the Lockout. They traded outfielder Tyler Naquin and relief pitcher Phillip Diehl to the Mets on Thursday.

The Reds could make a move before the Tuesday deadline.

Jesse Rogers was a contributor.