Now that the Dodgers have finally completed the Manny Machado deal, they've managed to fill a hole that… they may not have actually had. Chris Taylor is no Corey Seager, but he's having an above-average season, with a .332 on-base and a .454 slugging percentage. He's not going to lose his job, so when the multi-positional Taylor finds a new home, it'll take time away not only from the disappointing John Forsythe, but perhaps also Player Page for Max Muncy, Joc Pederson, or Alvin Toles. They've strengthened a strength. It's a good problem to have.
Everyone else may not be so fortunate, both in terms of not having the same depth and -- most crucially -- no longer having access to Machado, who will almost certainly be the best player traded before July 31. The Dodgers just gained on two fronts.
Still, anyone who's in it to win it is going to make some moves to fill some problem spots. We can figure where those issues are by using FanGraphs' projected values for the remainder of the season, and ID the positions on contenders that fall far short of average. We'll look at any position projected to receive less than 1 WAR for the rest of the year, weed out non-contenders and some that just aren't happening -- Colorado's Ian Desmond has hit .287/.342/.585 since the start of June, for example, making the first base upgrade they've needed for so long seem unlikely -- and go from there.
For pitchers, we'll look at rotations expected to get 4 WAR or fewer; for relievers, well, every team could use a reliever or two, so we won't focus on them here. 
These aren't all the needs. They're just the biggest ones.
Brewers: middle infielders and rotation
Lots of teams could have used Machado. The Brewers could have really, really used him, because their middle-infield situation is grim. Their shortstops are hitting all of .212/.264/.302, second-worst in baseball, and now that young Orlando Arcia is back in the Minors again, journeyman Tyler Saladino is the starter. It's not much better at second, where Jonathan Villar, Brad Miller, and friends have hit just .241/.296/.361, the 8th-weakest mark at the position.

Between the two spots, the Brewers have hit just .241/.296/.360. It's the 30th-ranked mark out of 30 teams. There may not be perfect answers here, but expect to hear a lot about James Dozier, Whit Merrifield, Asdrubal Cabrera, and maybe Jose Iglesias over the next week-plus.
They could also use a rotation upgrade, especially since Jimmy Nelson can't be counted on at all this year, but the infield situation has to be the priority.
D-backs: middle infielders
Take everything we said about the Brewers and repeat it here, which is why we'd pegged Arizona as a perfect home for Machado earlier this month. D-backs shortstops, primarily Nick Ahmed, are hitting just .230/.287/.430; second basemen, led by Ketel Marte, are at just .243/.328/.419.
The difference here is that Arizona won't go for just anyone. Ahmed's defense is considered to be very good, so there's no point in adding a similar Iglesias type. It doesn't help that third baseman Jake Lamb isn't hitting either, at just .229/.314/.365. The best fit here might be Minnesota's Eduardo Escobar, who has an MLB-leading 35 doubles to go with a .271/.327/.507 line, and like Machado, can play either shortstop or third.
Phillies: shortstop
"Young contending NL team needs left side infield help" is becoming a recurring theme, and we haven't even made it to Atlanta yet. You can understand why Philadelphia was so interested in Machado, because it's been a struggle on the left side. Shortstop was supposed to be manned by J.P. Crawford, but it's mostly been Scott Kingery instead, and neither has been productive: the .238/.286/.352 line from Phillies shortstops has led to a 71 wRC+, third-weakest in baseball.
It's fair to add the inconsistent Maikel Franco to this list, too, though it's unclear if an upgrade is out there. Mike Moustakas (.249/.306/.466) is a bigger name, but he hasn't actually out-hit Franco (.269/.317/.459) this season, either. Escobar might work here, too.
Braves: third base
For what it's worth, Moustakas hasn't out-hit Johan Camargo (.248/.346/.422), either, though a move here could free up the versatile Camargo to play other spots, too. (Camargo has been fine, but he appears here mostly due to his limited track record.) The Braves will probably focus on a reliever, but there's scenarios where they try to add some left-side infield help as well. Escobar would be an intriguing fit, perhaps if packaged with an underrated reliever like Thomas Pressly, though Atlanta could just call up prospect Austin Riley, too.

Rockies: corner outfielders
The Rockies somewhat surprisingly found themselves just two games out of first place at the break (though still in third place), and Desmond's recent streak probably means they won't go for a first baseman. While they could always use pitching, we're going to focus here on the same issue they've had for a few years now: weak corner outfielders on either side of Charlie Blackmon.
2018 has played out a lot like 2017 in that regard, as the talented David Dahl has been unable to stay healthy, and neither Gerardo Parra in left or Carlos Gonzalez in right has been all that productive. Colorado left and right fielders combined have hit .276/.320/.430, which on a park-adjusted basis is second-weakest in the game. They'll probably focus on bullpen help instead of this, but Adam Duvall, Derek Dietrich, or Avisail Garcia could potentially fit.
Indians: center and right field
Cleveland has a stud third baseman, one reliable outfielder, and a ton of bullpen problems -- at least before trading for Brad Hand and Adam Cimber -- so they're something like the Midwest Rockies, if the Rockies also had Corey Kluber, Trevor Bauer, Carlos Carrasco, and Mike Clevinger. While they'll also focus on relief, they could badly use a pair of outfielders, too. It was clear entering the season that what they had wasn't going to be enough, and it's not.
While Michael Brantley has been strong in left, the center and right field grouping of Bradley Zimmer, Lonnie Chisenhall, Tyler Naquin, and Brandon Guyer have combined to hit all of .241/.299/.338, the lowest mark of any team. They don't need to worry about an upgrade to win the weak American League Central, but it's hard to see them making noise in October like that. Any of the names mentioned above for Colorado could work, plus Detroit's Nicholas Castellanos.
A's: starting rotation
That's right, the A's are buyers, or at least they ought to be, as they're only three games behind Seattle for the second AL Wild Card spot. While they could use an outfield bat too, the bigger issue here is in the rotation, which is projected to be in the bottom third the rest of the way.

One problem here is that the available starting pitching market is underwhelming. Then again, the A's don't need a deGrom-level ace to upgrade. Pitchers like J.A. Happ, Cole Hamels, Nathan Eovaldi, Tyson Ross, won't quite have that impact, but they'd still be welcome additions to a unit that currently includes journeymen Edwin Jackson, Brett Anderson and Trevor Cahill.
Mariners: starting rotation
Speaking of those Mariners, they have a ton of uncertainty of their own in the rotation, although they've generally performed okay. (They have the 15th-best ERA so far, and they're projected to be the 15th-best group going forward.) The problem here is that Felix Hernandez and James Paxton are both dealing with minor back injuries, and Hernandez (5.13 ERA) hasn't really been that effective anyway. Throw in the relatively limited track record of Wade LeBlanc and Marco Gonzales sustaining success, and you can see why some added depth here would be a big need -- especially if Seattle manages to get a starter that might otherwise have interested Oakland. They'll be in on the same names that the A's are.
Red Sox: second base
Dustin Pedroia got into just three games and may miss the remainder of the year. Brock Holt has been okay, but Eduardo Nunez hasn't; Red Sox second basemen have a line of just .254/.297/.351, the sixth-weakest at the position. The recent Minor League signing of Brandon Phillips isn't going to move the needle, so Dozier or Cabrera may find themselves in Boston by the end of the month.
Nationals: catcher
Matt Wieters hasn't had a league-average hitting season of at least 300 plate appearances since 2012, and he missed a huge chunk of the first half with a hamstring injury. Nationals catchers, largely Pedro Severino and Spencer Kieboom, have hit just .185/.270/.270, the weakest line of any backstops, and there hasn't been a less productive National League catching group in at least a decade. Yes, they need an upgrade.
The larger question here is if they'll play well enough out of the gate to be buyers, but the fit here is the same one that it's always been: old friend Wilson Ramos, currently sidelined by a minor hamstring pull in Tampa Bay. Otherwise, there's relatively limited catching depth to be had, unless they pull off the long-rumored major move for J.T. Realmuto.