With new rules prohibiting trades facilitated by waiver claims after the July 31 Deadline, teams no longer can make an impact move like the Astros did when they put the finishing touches on a World Series championship club by dealing for Justin Verlander in August 2017.

There still are ways for teams to give their rosters a boost in August and September, the simplest and least expensive of which is to promote prospects from their farm systems. After the Athletics promoted then-anonymous Ramon Laureano on Aug. 3 last year, he provided an offensive and defensive spark that helped them secure a Wild Card berth.

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Contenders already are starting to look for help from within. The Brewers have installed Trent Grisham in their outfield, the Dodgers have added Dustin May to their rotation and the Rangers announced plans to promote Kolby Allard (acquired from the Braves last week in exchange for Chris Martin) and start him Friday against Milwaukee. Here are 10 more prospects who could help clubs make a playoff push, ranked based on a combination of talent and opportunity:

1. Kyle Tucker, OF, Astros (HOU No. 1, MLB No. 13)

The Zack Greinke trade made the Astros the favorites to win the World Series and they were able to swing the deal without trading their top prospect, who's chasing a 30-30 season in Triple-A after consecutive 20-20 years. Houston could enhance its chances by playing Tucker in right field over Josh Reddick, who continues to trend downward.

2. Ian Anderson, RHP, Braves (ATL No. 3, MLB No. 34)

The Braves promoted their three best prospects to Triple-A on Monday, and Anderson has a clearer path to contributing in Atlanta down the stretch than outfielders Cristian Pache and Drew Waters. The back of the Braves' rotation has been shaky and Anderson could be next in line for a shot after 2017 first-rounder Kyle Wright had a rough July audition and Kevin Gausman got waived on Monday. Anderson has the potential for three plus pitches and his command continues to improve.

3. Gavin Lux, SS/2B, Dodgers (LAD No. 1, MLB No. 10)

If this list was based solely on talent and readiness, Lux would rank No. 1. He has no clear opportunity to 2019 playing time with the Dodgers, whose roster only will get more crowded once David Freese, Kiké Hernandez and Chris Taylor return from injuries. That said, Lux might be their best present option at second base and he's hitting .456/.535/.846 since arriving in Triple-A in June.

4. Deivi Garcia, RHP, Yankees (NYY No. 1, MLB No. 66)

While the Yankees are running away with the American League East, it remains to be seen if they have enough rotation depth to win the World Series. Garcia's electric stuff could help in that regard, as he can miss plenty of bats with a mid-90s fastball and a dastardly curveball, and it also would play well out of the bullpen.

5. Nate Lowe, 1B, Rays (TB No. 8)

The odd man out after the Rays acquired Jesus Aguilar at the Trade Deadline, Lowe got sent to Triple-A last Thursday. He batted .294/.365/.510 with five homers in his first 30 big league games and should be back in Tampa Bay soon because he's better than fellow lefty-hitting first baseman Ji-Man Choi (who's out of options).

6. Jorge Mateo, SS/2B, Athletics (OAK No. 4)

Mateo has had a resurgent year in Triple-A, batting .295/.334/.520 with 55 extra-base hits (17 homers) and 21 steals in 100 games. Once he recovers from an ankle injury that landed him on the injured list, his combination of elite speed and sneaky power would give the A's an upgrade over Jurickson Profar at second base.

7. Carter Kieboom, SS/2B, Nationals (WAS No. 1, MLB No. 22)

Nationals second baseman Brian Dozier is hitting for power but doing little else, and Kieboom is a better all-around if less established option who homered in two of his first three big league games in late April. At the very least, he'd be a useful player off an injury-depleted bench.

8. Jesus Luzardo, LHP, Athletics (OAK No. 1, MLB No. 19)

Luzardo already would be ensconced in Oakland's rotation if he hadn't come down with shoulder and lat strains this year. He's healthy again and still one of the best lefty pitching prospects in baseball, so he could help the A's -- though they might try to mitigate the risk and use him out of the big league bullpen for 2019.

9. Forrest Whitley, RHP, Astros (HOU No. 2, MLB No. 17)

Whitley began the year as the game's top pitching prospect, only to battle his command and shoulder fatigue for much of the season. He's healthy and starting to look like his old self again, and his arsenal of four plus or better pitches could handle some high-leverage relief innings in October.

10. James Karinchak, RHP, Indians (CLE No. 21)

With a mid-90s fastball and 12-6 curveball, Karinchak has struck out 51 in 20 1/3 Minor League innings this summer. He has been sidelined by hamstring injuries and his control has been off since he returned, but he could be a bullpen weapon for the Indians once he relocates the strike zone.