11:19am: Both teams have officially announced the trade. To clear 40-man roster space for Arraez and Kilian, the Phillies have designated catcher Payton Henry for assignment. They reinstated right-hander Lou Trivino from the 15-day injured list and designated him for assignment as well.

8:48am: The Phillies are upgrading their offense in a big way, as they’ve acquired second baseman Luis Arraez and reliever Caleb Kilian from the Giants. The Giants receive right-handers Ramon Marquez and Marty Gair in return. The Giants’ 40-man roster stands at 38 players with this move.

Arraez was seen as an obvious candidate to be traded. San Francisco is 12 games out of a Wild Card spot and open for business on their rental players, as well as some more expensive contracts. There was some talk of the Giants extending Arraez, but while he himself expressed interest in a deal, formal extension talks between the two sides never materialized.

Long known as the game’s premier contact hitter, Arraez signed a one-year, $12MM pact with the Giants this offseason. He reportedly received multi-year offers as well, but took the Giants’ deal because they planned to play him at second base, as he desired. That ended up working out beautifully. Defensive metrics have typically been bearish on Arraez regardless of position, but this year, he’s surprisingly been worth 11 Outs Above Average at the keystone as well as +9 by Fielding Run Value. The latter is the best mark of his career. While Defensive Runs Saved (-2) still takes a negative view, it’s clear that Arraez has improved significantly as a fielder.

In addition to the glovework, Arraez has continued to hit at his usual levels, if not better. Through 464 plate appearances, he’s batting .324/.360/.440 with a wRC+ of 120, meaning he’s 20% better than the average hitter. Despite only walking 5.4% of the time, Arraez is somehow striking out even less, running a 4.5% strikeout rate that’s easily the best among qualified hitters. He currently ranks second behind the Marlins’ Otto Lopez in hits (136) and second to the Astros’ Yordan Alvarez in batting average (.324). He’s also chipped in ten stolen bases.

By maintaining his old-school hitting approach and turning himself into a competent defender, Arraez positioned himself as arguably the top hitter on the trade market, and certainly the best lefty. He unsurprisingly drew interest from no less than seven teams, including a trio of AL East clubs and Arraez’s old friends in the Padres. In the end, the Giants will cash in on their best trade asset by shipping him and Kilian to Philadelphia in exchange for the two prospects.

The positional fit in Philadelphia is an interesting one, as they currently have Bryson Stott manning second base. Stott is batting .252/.317/.407 with a 98 wRC+, 18.3% strikeout rate, and 8.3% walk rate. It’s a more standard profile than the extreme contact approach followed by Arraez, and Stott complements it with decent glovework of his own. He’s been worth 6 OAA at second base this year and has now drawn positive OAA ratings in each of his five big league seasons. FanGraphs values him at 2.3 fWAR so far in 2026.

Arraez told reporters last month that he was hopeful of staying at second base in the event of a trade. He did not have a no-trade clause, so he could not directly control that outcome. Nonetheless, the Phillies will oblige by installing Arraez at second base, according to Matt Gelb of The Athletic. That alignment could see Stott move to the hot corner, where he’d take over for the incumbent in Alec Bohm. The latter is having a replacement-level season in his final year of club control, running a 77 wRC+ in 437 plate appearances and grading out poorly on defense (-8 DRS and -6 OAA). If he is indeed pushed out of a starting role in Philly, Bohm could be dealt by today’s 5pm Central deadline, though he wouldn’t get much of a return.

Another possibility is that the Phillies hold onto Bohm, slide him over to first base, and move Bryce Harper back to the outfield. Harper began playing first base in 2023 after recovering from Tommy John surgery, and he’s remained there ever since. He’s previously been willing to move to the outfield if needed, though president of baseball operations Dave Dombrowski resisted those offers, per Scott Lauber of The Philadelphia Inquirer. That said, the two had another conversation on Friday in Baltimore, and with Arraez now in the fold and some realignment needed, they could revisit the idea of playing Harper in the outfield. It’s also possible the Phillies keep Harper and Bohm at their positions and move Stott to the outfield, per Gelb.

However the defense shakes out, the addition of Arraez gives a major jolt to a Phillies offense that has struggled in 2026. The team’s overall 92 wRC+ ties for third-worst in the majors, and while they’ve posted a 97 wRC+ since the All-Star break, that still checks in below average. As a team, the Phillies strike out at a 23.6% clip that ranks seventh-worst, and their .237 batting average is tied for eighth-worst. Arraez will help solve both of those problems. He figures to slot in near the top of the lineup and put the ball in play at elite rates in front of Harper, Kyle Schwarber, and other power hitters.

The Phillies also get a solid reliever in Kilian to reinforce their bullpen. The 29-year-old righty signed a minor league pact with San Francisco over the offseason. He made the bullpen out of spring training and has thrown 44 1/3 innings with a 4.26 ERA, 27.5% strikeout rate, and a stellar 49.1% ground ball rate. He walks a bit too many hitters, but estimators like SIERA (3.42) and xERA (3.33) suggest he’s a more talented pitcher than the surface-level numbers indicate.

While their offense has struggled, the Phillies’ bullpen has been one of the game’s best. Jhoan Duran is on the shortlist for best closers in the game. Jonathan Bowlan and Orion Kerkering both have ERAs under 3.50 for their relief work. Kilian gives them another right-handed option to complement those arms, and the Phillies will look to further harness his strikeout potential while keeping up the ground balls and cutting back on the free passes. Kilian has less than a year of service time and can be controlled through the 2031 season.

Looking at the Giants’ return, Marquez is the clear headliner of the package. He signed with the Phillies as an international free agent out of Mexico in January 2025, and he’s worked 59 innings with a 1.69 ERA in 2026, the last 30 of which have been at the High-A level. Marquez is striking out an incredible 41.9% of opposing hitters while generating grounders more than 50% of the time. He was ranked at No. 4 in the Phillies’ system according to MLB.com. The Giants were clearly intrigued by his mid-90s fastball and strikeout potential, and they’ll see if Marquez can maintain them as he works toward the higher levels of the minors.

Gair is an unranked, lottery ticket prospect. The 23-year-old was a late-round draft pick in 2023. He has an impressive 44.6% strikeout rate in the low minors this year, though he could stand to improve his control, as is common with young arms. Marquez is the higher value of the two, but Gair is nonetheless an intriguing add to the lower ranks of the Giants’ system.

Arraez’s contract with San Francisco included a $10MM salary for 2026, the other $2MM being a signing bonus. About $2.97MM remains to be paid out, which the Phillies will take on in addition to the $252.7K left on Kilian’s near-minimum salary. The $3.22MM in additional salary brings the Phillies’ cash payroll to around $290.9MM and their luxury tax number to $321.4MM, as seen in MLBTR’s new Payroll Tracker. (Note: Those figures do not account for reliever Brooks Raley, who was also acquired this morning). The team has paid the luxury tax in the last three seasons and is well over the top tier of penalization, so they’ll be charged an additional 110% on their commitments to Arraez and Kilian.

Jeff Passan of ESPN was the first on Arraez being traded. Bob Nightengale of USA Today was first on the inclusion of Kilian, Marquez, and Gair. Photos courtesy of Darren Yamashita, Robert Edwards, Imagn Images.