SAN DIEGO -- Evidently, the Padres weren't done shopping for starting pitching.

San Diego landed right-hander Joe Musgrove in a three-team, seven-player deal involving the Mets and Pirates on Tuesday, sending lefty Joey Lucchesi to New York and a package of four prospects headlined by Hudson Head to Pittsburgh. The Pirates also will get a prospect from the Mets.

? Why Musgrove is a breakout candidate

It's the latest move in a frantic Padres offseason that has seen Blake Snell and Yu Darvish arrive to bolster the San Diego rotation. Here's the trade in full:

Padres get: RHP Joe Musgrove
Mets get: LHP Joey Lucchesi
Pirates get: OF Hudson Head, RHP David Bednar, LHP Omar Cruz, RHP Drake Fellows from the Padres and C/OF Endy Rodriguez from the Mets

What the Padres got
Musgrove, a native of the San Diego suburb of El Cajon, Calif., grew up a Padres fan. Needless to say, he¡¯s thrilled to be returning to his hometown. Speaking Monday on the reports that he¡¯d been traded, Musgrove told MLB.com¡¯s Adam Berry:

¡°It¡¯s extremely exciting to be able to play in the city that I developed my love for the game. It¡¯s always been a dream -- I¡¯m sure for every player -- to get a chance to represent their city and play in their hometown, especially right now at a time where I feel like the Padres have never been better. I think about all the guys that I¡¯m going to be surrounded by in that clubhouse, not just the staff and the recent pitchers they¡¯ve added, but some of the dynamic position players that they have, guys like [Manny] Machado, [Eric] Hosmer, [Fernando] Tatis [Jr.].¡±

Musgrove figures to play an important role in that group¡¯s quest to bring a World Series to San Diego. In five big league seasons, he owns a 4.33 ERA, including a 3.86 mark in eight starts in 2020. Musgrove missed four weeks in ¡¯20 with right triceps inflammation. But he recovered and finished the year by twirling consecutive starts with 10-plus strikeouts, three hits and no runs.

After a strong finish, Musgrove is a clear breakout candidate for 2021. His underlying metrics were excellent in '20, with a punchout rate and an average exit velocity that ranked in the 90th percentile or better. Essentially: Musgrove strikes out a lot of hitters with two excellent breaking pitches. And when those hitters make contact, they don¡¯t hit the ball very hard.

The Musgrove deal is yet another example of the busy Padres looking for a boost in both the short- and long-term. They've made a flurry of moves this winter, but none have been to acquire a player with only one year of control. Musgrove can become a free agent after the 2022 season.

How it fits
Even with the December additions of Snell and Darvish, the Padres were looking for some help in the middle of their rotation. They lost right-hander Mike Clevinger for the 2021 season because of Tommy John surgery, and they sent fellow righty Zach Davies to the Cubs in the deal for Darvish.

Musgrove fits the bill. He should slot in nicely behind a big three of Darvish, Snell and Dinelson Lamet. Good luck finding a better 4-5 combo than Musgrove and Chris Paddack.

¡°I'm thrilled," Musgrove said. "Those are guys that have all established themselves and done things at the big league level that are recognizable. ... Knowing I¡¯m going to have the ability and the access now to be in the clubhouse with them every day and watch them throw their bullpens and pick things from them that they¡¯ve done along the way that have made them who they are, it¡¯s extremely exciting.¡±

Notably, Tuesday's trade likely means that MacKenzie Gore, MLB Pipeline¡¯s No. 3 overall prospect, will open the season in the Minors. Fellow left-handers Ryan Weathers and Adrian Morejon might join him there (though they¡¯d both presumably be given the chance to compete for a bullpen spot).

Of course, there are still questions surrounding the health of Lamet, who had a platelet-rich plasma injection in his right elbow in October. (Lamet has begun throwing and has reported no issues, but privately team officials acknowledge that nothing is certain until he pitches in a game setting.) Plus, Paddack regressed last year after his breakout 2019 season. As such, Preller¡¯s quest for rotation depth seems like a sensible one.

"What we've tried to create is a staff that's not just five deep, but we want to look up and be eight, nine, 10 deep of real Major League starters," Preller said last month. ¡°We¡¯ve talked about it a lot. You can never have enough true front-of-the-rotation-type Major League starters. ¡­ What we¡¯ve tried to do is: Every single day we have somebody we feel like could be that ace type.¡±

What they gave up
Lucchesi is the most recognizable name of the five players the Padres gave up. He spent two full seasons in the big leagues with San Diego, posting a 4.08 ERA in 2018 and a 4.18 mark in '19. But Lucchesi took a step back in '20, and he only pitched 5 2/3 big league innings as the team settled on bullpen days during his turn in the rotation instead.

Ultimately, Head is the biggest prize from the Padres' package. Head signed for $3 million in 2019, then a record for a third-round Draft choice, and he batted .283/.383/.417 in Rookie ball. The Padres thought enough of the 19-year-old Head to include him in their 60-player pool this year.

Head impressed against quality competition at the team's alternate site, and the Padres have always loved his smooth lefty swing, which should eventually produce some power. He has the potential to become a five-tool big league outfielder, but the Padres felt that was a worthwhile price to acquire a proven big league rotation talent.

Meanwhile, Bednar could become a serviceable relief weapon, and Fellows and Cruz bring their own upside on the mound. But Head should be viewed as the centerpiece of the Pirates' return. Pittsburgh also landed catcher/outfielder Rodriguez from the Mets -- essentially in a one-for-one swap for Lucchesi.

What's next
Aside from perhaps some Minor League depth, the Padres are most likely finished looking for starting pitchers this winter.

That leaves two other items on the agenda: bullpen and bench.

In both areas, San Diego already has an assortment of in-house options. But according to sources, Preller would still like to bolster those groups before the season begins.

The Padres return starters at all eight positions and added infielder Ha-Seong Kim earlier this winter, so there isn't any regular playing time available. But San Diego could use a versatile utility man with experience playing the outfield, and a reunion with Jurickson Profar remains possible.

As for the bullpen, the price on the top available relievers has been too steep for the Padres' liking. Despite the losses of Trevor Rosenthal and Kirby Yates to free agency, they don't see it as imperative to add a closer. It's possible San Diego adds a middle-innings weapon instead, with Emilio Pag¨¢n or Drew Pomeranz sliding into the closer role.

But it's also possible that the newest rotation addition clears the way for Morejon and Weathers, two electric young arms, to slot into those middle innings.

MLB.com reporter Adam Berry contributed to this report.