This story was excerpted from Brian McTaggart's Astros Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

Now that the Astros are back in firm grip of first place in the American League West after sweeping the Mariners last weekend, our attention turns to the Trade Deadline. Astros general manager James Click has said the Astros were going to be aggressive, and there are some clear needs on the club despite its 108-win pace.

Through play Sunday, 19 of 30 teams were either firmly in a good spot to make the playoffs or within five games of a Wild Card spot, meaning there are lot of teams in contention and many of them will be looking to add pieces. If you don’t get the player that you covet today, another team might get him tomorrow. The Astros, of course, realize this and will be looking to improve their roster prior to Tuesday’s Deadline.

Let’s take a closer look at where the Astros should be considering upgrades/additions:

Backup catcher
It’s becoming increasingly unlikely the Astros will see Jason Castro return from his latest knee injury, and even if he does, it’s still a spot at which they could use an upgrade. Martín Maldonado will get the lion’s share of the playing time in the playoffs, but having a backup option who could pinch-hit or allow manager Dusty Baker to pinch-hit for Maldonado in certain spots -- or make more starts -- would be beneficial. Catching prospect Korey Lee has a bright future, but another veteran backstop is needed for the present.

Ideal fit: Christian Vázquez, Red Sox. First, the Red Sox need to decide if they’re buyers or sellers. If they’re sellers, the Astros should target Vázquez, a solid defensive catcher who’s better than average offensively. He’s a free agent at season’s end.

Others: Elias Díaz (Rockies), Sean Murphy (A’s).

Offense
Left fielder Michael Brantley has been out since June with a shoulder injury, and the Astros have gotten lackluster production in center field and first base. There isn’t one player who could fill all three of those holes, but finding an outfielder who can play two positions or a first baseman who could play the outfield would go a long way in solving that problem. The Astros also must be concerned about slugger Yordan Alvarez, who’s lingering hand issue isn’t going away. 

Ideal fit: Josh Bell, Nationals. A switch-hitter, Bell was slashing .304/.388/.494 with 13 homers and 51 RBIs through Tuesday and could provide a huge upgrade for the Astros offensively at first base, where Yuli Gurriel has struggled. Bell, a free agent at the end of the season, has also played the corner outfield spots.

Others: Andrew Benintendi (Royals), Trey Mancini (Orioles), Brandon Drury (Reds), David Peralta (D-backs), Ian Happ (Cubs), Seth Brown (A’s).

Bullpen
Who doesn’t need a bullpen arm for the stretch run? And there are lots of them available. Last year, the Astros traded for four relief pitchers at the Trade Deadline: Kendall Graveman, Rafael Montero, Phil Maton, and Yimi Garcia. Montero and Maton remain as key relievers for Baker, along with closer Ryan Pressly and setup men Ryne Stanek and Héctor Neris. They could use another proven arm and perhaps a lefty more than anything.

Ideal fit: Andrew Chafin, Tigers. A southpaw, Chafin has excelled in manager A.J. Hinch’s bullpen in Detroit, posting a 2.64 ERA and 1.08 WHIP in his first 36 appearances. He’s held right-handers to a .490 OPS and lefties to a .637 OPS. He has a $6.5 million player option for next year but would basically be a rental.

Others: David Robertson (Cubs), Michael Fulmer (Tigers), Matt Moore (Rangers), Joe Mantiply (D-backs), Joe Jiménez (Tigers), David Bednar (Pirates).