Tucker and Kratz are moving down while Gattis and new call-up Tony Kemp are moving up.
I'm a bit torn on Tucker moving down; while he has potential to be a good hitter and showed it last season, something is not right this season and lately (that is, the month of May) he has not hit much at all. Still, Tucker has been more or less a part-time player, with a mere 89 PA's as of today. Was it a numbers game in terms of options and resources invested? Of course.
I'm not sure why Tucker and not Marisnick, though, or why Marisnick wasn't sent down in another move. A part-time player with even fewer appearances (and a trip to Fresno already taken), Marisnick is a very bad hitter whose defense doesn't make up the difference. If he were merely below average, I'd have no problem; after all, this team has plenty of below average hitters who haven't pulled their weight so far. Marisnick is so poor that his OPS+ is below zero, which is just unacceptable. For the team to not deal with this is short-sighted and makes it look like Tucker's demotion was scapegoating.
So while neither Tucker nor Marisnick have gotten enough PA's to be considered full-time, they have woefully underachieved when given playing time.
Evan Gattis returns from Corpus, newly invested in his role as backup catcher. When he was up with the Astros previously, he was similar to Tucker in terms of output. As DH or backup catcher, I would not expect great numbers from him because he will not likely get enough PA's to establish a steady groove.
Tony Kemp comes up from Fresno with an ability to get on base. For this team, that just might be enough to get him playing time, especially if he can bolster the bottom of the lineup. The 7-8-9 hitters have been notoriously bad not only in terms of hitting with RISP, but in getting on base to start rallies in the first place. While I don't expect Kemp to duplicate his gaudy OBP from Fresno in Houston, pretty much anything will help.
Of course, the elephant in the room and the reason for Kemp's promotion is Carlos Gomez. Were Gomez playing well, comparable with even White or Rasmus (who have both fallen off in recent weeks), there wouldn't be much of a problem. I don't expect Gomez to hit like Altuve, Springer, or Correa. I don't really expect a Gold Glove caliber effort in CF, either, though it'd be nice. What I do expect is for him to be competent offensively and defensively. So far, he's been competent in neither area, grounds into too many double plays and strikes out far too frequently. Much like other hitters on the team who have been scuffling, his approach is ass-backward, swinging as hard as he can more often than not and usually not making contact. It seems easy to say that he should shorten his swing and attempt to hit more pitches to the opposite field, but much more difficult for it to bear fruit.
Gomez has 132 PA's through 34 games so far. For his effort he has produced a .486 OPS, not only one of the worst on the team, but magnified greatly by the fact that he is regularly penciled into the lineup yet rarely does anything while in it.
If Kemp were coming up to solve the problem in CF, the Astros would still have an issue at 3B. The general platoon at 1B of White and Marwin Gonzalez is okay for now, tolerable because both guys are hitting above average (again, as of today). All that says is that 1B is not as big a problem as 3B or CF, but the team could certainly be getting more production out of the position, especially given the expectations.
Also, it's worth noting that neither of the moves affect the rotation or bullpen. In the case of the starting rotation, the solution might just be to wait it out and see if they can give up fewer runs as a whole. The bullpen has been solid overall, despite having a rough go of it in Boston. I don't expect that kind of struggle, because few teams are as offensively gifted as Boston appears to be.
Still, the rotation and bullpen aren't so good that each and every guy can be thrown out there and expected to perform well. It has to be managed carefully. So far, I'm not sure that Hinch is the right guy to do that. There have been a lot of questionable decisions in terms of managing the bullpen and making out the lineup every day. While I tend to think that it's up to the players to get out of the extended slump most of them find themselves in, it would be beneficial if Hinch could put them in better positions to win.