Jean Segura waived his no-trade clause Monday, one of the final steps in completing a multiplayer deal that will send the all-star shortstop from the Seattle Mariners to the Phillies.

The trade, agreed to in principle late Sunday, represents the first big move of a possibly transformative offseason for the Phillies. Shortstop J.P. Crawford, formerly the Phillies' top prospect, is believed to be headed to the Mariners. Multiple reports have indicated that first baseman Carlos Santana is going to the Mariners, too. It’s likely the Phillies will be receiving at least one other player besides Segura.

Segura, 28, is attractive to the Phillies for several reasons, specifically his ability to make contact at the plate. He was the fourth-hardest hitter to strike out last season, with a 10.9 percent whiff rate. The Phillies struck out 1,540 times last season, second-most in the National League.

The move, which will be finalized once medical records are reviewed, is unlikely to preclude the Phillies from pursuing free agent Manny Machado. Although Machado prefers to play shortstop, he’s a much better third baseman, with one National League scout giving him an 80 ranking at third base compared to 55 at shortstop on the 80-to-20 evaluation scale. Segura also played 1,170 innings at second base in 2016, the best season of his career.

Regardless, the trade sends a clear signal to Machado, Bryce Harper, Patrick Corbin and other big-name free agents that the Phillies are serious about competing for a playoff spot next season, if owner John Middleton’s recent comments about being “a little stupid" about spending big money this winter didn’t already get their attention. Corbin could choose a team in the coming days after visiting with the Phillies, New York Yankees and Washington Nationals last week.

Crawford was long considered the Phillies’ shortstop of the future. Late in an injury-marred 2018 season that was supposed to be critical for the 23-year-old’s development, manager Gabe Kapler even said the Phillies had a “long-term vision” for Crawford. But a fresh start with the rebuilding Mariners might be exactly what Crawford needs to realize his potential.

The Phillies were shopping Santana heavily over the past few weeks, according to multiple sources, in an attempt to return Rhys Hoskins to his natural first-base position after a failed experiment in left field. The Colorado Rockies had interest in Santana, one source said, but were unwilling to take on the full weight of his salary. Santana is owed nearly $40 million over the next two seasons.

In seven major-league seasons, Segura is a .287 career hitter with a .731 on-base plus slugging. But over the past three seasons, he seemingly reached his peak, batting .308 with a .353 on-base percentage, .803 OPS and 75 stolen bases. It’s easy to see him slotting in atop the Phillies' order.

One NL scout recently regarded Segura as an “average,” but nevertheless “solid” shortstop with limited range who makes most of the plays he’s expected to make. Even average would be an upgrade for the Phillies. They finished with minus-146 defensive runs saved last season, the worst total since Baseball Info Solutions began tracking that metric in 2003. Segura ranked 10th among all shortstop last season with five defensive runs saved.

Segura has four years and $57 million left on a five-year, $70 million contract. He also has a $17 million team option for 2023. Segura received a $1 million assignment bonus from the Mariners for agreeing to waive his full no-trade clause and will retain his right to reject any trade while with the Phillies, according to a source.