It's already been a busy offseason for the Phillies, who have upgraded by trading for J.T. Realmuto and Jean Segura, and signing Andrew McCutchen and David Robertson.
But many feel there is still a big piece missing.
That would be Bryce Harper or Manny Machado, the two highest-profile free agents, both of whom remain available and both of whom have been connected to Philadelphia throughout the offseason. Looking at Harper, specifically, MLB Network insider Jon Heyman reported Sunday afternoon that "things are heating up" with the star outfielder and that the Phillies are seen as the favorite, although nothing is done yet.
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MLB.com's Mark Feinsand recently named the Phillies as one of two favorites to land the slugger, along with the National League East-rival Nationals. Washington is the only franchise Harper has known, but the Phillies might have the greater need and the stronger motivation. Speaking Thursday at Phillies camp in Clearwater, Fla., general manager Matt Klentak said his club will "continue to explore" signing another prominent free agent, such as Harper or Machado, and expressed his belief that the Phillies have "put our best foot forward with those guys so far."
With that context, let's take a look at what would happen if the Phillies did sign Harper -- just as we did for the Yankees earlier this week.
Where would he play?
By shipping off Carlos Santana in the Segura trade, the Phillies also opened up first base for Rhys Hoskins, who should be more comfortable defensively there. They then signed McCutchen to fill left field. That leaves a crowd of outfielders competing at the other two spots, primarily Odúbel Herrera, Nick Williams, Roman Quinn and Aaron Altherr.
Harper, should he sign, most likely would slide into right field, next to Herrera and McCutchen. That could displace Williams, acquired in the Cole Hamels trade, who over two Major League seasons has yet to establish himself as an indispensable piece. Since Herrera and Quinn are the best options in center, it's possible such a move could force a trade of Williams.

Where would he hit?
McCutchen, Realmuto and Segura all have strengthened a Phillies lineup that last season ranked 22nd in the Majors with a .707 OPS and tied for 21st with 677 runs scored. Even so, it's still not a group that is necessarily heavy on power, with only Hoskins having a recent 30-homer season.
Hoskins also bats right-handed, while Herrera and Williams are the only pure left-handed batters in the current projected lineup. Harper could slide right into the middle of the order, pairing with Hoskins as a one-two, left-right slugging combo. Here's how that might look:
1. César Hernández, 2B
2. Andrew McCutchen, LF
3. J.T. Realmuto, C
4. Bryce Harper, RF
5. Rhys Hoskins, 1B
6. Odubel Herrera, CF
7. Maikel Franco, 3B
8. Jean Segura, SS
9. Pitcher's spot
That's just one possibility, but manager Gabe Kapler would have no shortage of options. Segura could swap with Hernandez or join him at the top of the lineup. McCutchen could hit leadoff or move below the Realmuto-Harper-Hoskins trio, although his strength over the past two seasons has been patient at-bats and OBPs over .360. Whatever the exact order, Harper would be the centerpiece.

How would this affect 2019 projections?
The Phillies are exactly the sort of team that could use another significant infusion of talent. The Steamer projections available at FanGraphs have them at .500 in 2019, in fourth place in the NL East but just behind the Braves (82 wins) and Mets (85). Philly is part of a crowd of nine NL clubs projected at between 79 and 86 wins -- the latter figure good for the top Wild Card spot.
It's a similar story with Baseball Prospectus' PECOTA projections, where the Phillies fare a bit better (85-77) but still are tied for third in the division with the Braves, one of 10 teams between 80 wins and the 88 necessary for a Wild Card berth.
The point is, Philly is in a place where every additional victory could significantly affect its chances of qualifying for the postseason for the first time since 2011.
Harper is projected for roughly 5 wins above replacement (WAR), according to Steamer, while slashing .267/.399/.528 with 34 home runs. Meanwhile, even assuming 600 plate appearances each, Williams, Quinn and Altherr all project for less than 1 WAR. In other words, bringing Harper to Citizens Bank Park easily could mean a boost of four or five wins -- enough to push the Phillies from hopeful to favorite for a Wild Card spot, and into serious contention for the NL East.

What are some other long-term ramifications?
In terms of the Competitive Balance Tax, the Phillies still have plenty of room to operate without incurring any sort of penalty. The threshold for 2019 is $206 million, and Philadelphia currently stands at about $166 million, according to Roster Resource.
Furthermore, the only players the club is firmly committed to beyond 2021 are Aaron Nola, Scott Kingery and Segura, though Herrera, McCutchen and Jake Arrieta also will be retainable via team options. In the short term, the Phillies can accommodate an expensive contract. In the long term, they have flexibility and can build around Harper, Nola and Hoskins.
However, the Phillies would have to consider Harper's outfield defense, which rated quite poorly last season by advanced metrics. While there is reason to think Harper will bounce back in the short term, that defense could become an issue again over the course of a lengthy contract, especially if Hoskins becomes entrenched at first base -- unless the NL adopts the designated hitter by that point.