PHILADELPHIA -- The Jean Segura trade is an important first step in an important offseason for the Phillies.
The Phillies announced on Monday evening that they have acquired Segura, right-hander Juan Nicasio and left-hander James Pazos from the Mariners for first baseman Carlos Santana and shortstop J.P. Crawford. The Phillies surrendered no cash or prospects in the deal.
Segura, a two-time All-Star who rates as one of baseball's best shortstops in recent seasons, is an immediate upgrade to the left side of the Phillies' infield. With Santana removed from the roster, Rhys Hoskins can return to first base, and the Phillies maintain the financial flexibility to pursue free-agent superstars Manny Machado and Bryce Harper, as well as left-hander Patrick Corbin, and make other potential improvements through trades.
"To add an All-Star shortstop like Jean Segura moves the needle quite a bit, probably several wins," general manager Matt Klentak said on a conference call. "I think that's important. I think as we're trying to improve on an 80-win team to try to put ourselves in playoff contention, we needed to identify the areas where there are opportunities to make improvements like that, and I think shortstop was an area for us."

Segura, 29, hit .304 with 10 home runs, 63 RBIs and a .755 OPS in 632 plate appearances last season with Seattle. He ranked ninth among 21 qualified shortstops with a 3.8 Wins Above Replacement, according to FanGraphs. Phillies shortstops had a 0.7 WAR, which ranked 27th in baseball. Segura ranks seventh among shortstops in WAR over the past three seasons; Phillies shortstops ranked 22nd in that span. Segura is regarded as an above-average defender and is remarkably difficult to strike out, which was an issue last season for the Phillies. His strikeout rate (10.9 percent) ranked fourth-lowest out of 140 qualified hitters.
• How Segura fits in Phillies' lineup
Segura is signed through 2022 and making a club-friendly $14.25 million each of the next four seasons, with a $17 million club option or $1 million buyout for 2023. The Phillies unloaded the remaining $35 million on Santana's contract, which gives them plenty of opportunities to make more big moves before Spring Training.

Sources told MLB.com that the Phillies still plan to pursue Machado, despite the fact that he and Segura play the same position. Machado could be convinced to play third base, or Segura could be moved to second base.
• Phils still in for Manny, Harper after Segura deal
"Whether we're talking about roster flexibility or payroll flexibility or positional flexibility, flexibility is a big part of what we do in this game," Klentak said. "This did not have a huge impact on the payroll, and it allows us to stay flexible. We can continue to explore deals in other areas knowing that we should have some payroll room to address that if necessary. But if it comes in the form of a trade, we can pursue that as well. This was a trade that accomplished several things for us, one of them being that it allows us to stay flexible for the rest of the offseason."
Nicasio, 32, posted a 6.00 ERA in 46 appearances, but he also struck out 53 batters and walked just five in 42 innings. He had a 2.99 FIP, which the Phillies believe is an excellent indicator of a pitcher's future success. The Phillies are familiar with Nicasio, having claimed him off waivers from the Pirates in August 2017, though they traded him a week later to the Cardinals. He will make $9.25 million next season.
Pazos, 27, had a 2.88 ERA and a 3.60 FIP in 60 appearances. He struck out 45 and walked 15 in 50 innings.
"I think we add a bounceback reliever in Nicasio, who we believe has a chance to be pretty good, and we added some important left-handed pitching depth to our bullpen, which was another offseason goal for us," Klentak said. "In a lot of ways, we checked off a lot of boxes with this trade."

Santana and Crawford entered last season as important pieces of the Phillies' future. The Phillies signed Santana to a three-year, $60 million contract last December, touting his ability to reach base and hit for power, and his defensive prowess as reasons for the deal. They believed Hoskins could handle himself adequately in left field, too. But none of those things worked as planned. Santana suffered his worst offensive season since 2015 -- although he posted numbers near his career averages after an abysmal April -- and played league-average defense, while Hoskins graded out as one of the worst outfielders in baseball.
"Importantly, it allows us to move Rhys Hoskins to first base, and we think, in turn, that's going to improve our team defense," Klentak said.
The Phillies selected Crawford in the first round of the 2013 Draft. Once recognized as one of the top prospects in baseball, the 23-year-old hit. 214 with three homers, 12 RBIs and a .712 OPS in 138 plate appearances last season. After a terrible start, he posted an .848 OPS in his final 113 plate appearances, although they were spread out over several months because of injuries.
This is the fourth time Segura has been traded in his career, and the third time in less than three years. He had problems with the Mariners last season, most notably getting into a scuffle with teammate Dee Gordon. Manager Scott Servais had his issues with Segura, too, but the Phillies said they are comfortable with Segura and his impact in the clubhouse.