This is the weakest division of farm systems, with the Los Angeles Angels no longer 30th overall but not far above it, the Seattle Mariners trading away much of their prospect depth to improve the major league club for 2017-18, and the Oakland Athletics slowly building back up after they traded away some top prospects in 2013-14. The Texas Rangers' system has some potential stars at its lowest levels, but the Cole Hamels and Jonathan Lucroy trades, compounded with a slew of promotions the past two years, have left them dry above A-ball.

That means the Houston Astros, already competitive the past two years, have the best system in the division in addition to a strong, young big league roster, with some very big arms on the way to help keep the rotation going even when current starters depart.

Here are the top prospects in the AL West:

Houston Astros: Top prospects report

Lower-round steals, investment in the international market and shrewd deals, including one for its top prospect, keep Houston's system strong.

Los Angeles Angels: Top prospects report

Once the worst farm system in baseball, the Angels are slowly improving with high-floor college guys, high school prospects and high-ceiling athletes.

Oakland Athletics: Top prospects report

After bottoming out during the team's last run of contention, Oakland's system is slowly making its way back, with many of its top prospects being shorter, right-handed pitchers.

Seattle Mariners: Top prospects report

With many high picks not panning out and other prospects being traded, the Mariners' system is on the downswing, with only one player in the top 100.

Texas Rangers: Top prospects report

Megadeals for Cole Hamels and Jonathan Lucroy have thinned the Rangers' farm system, and many of their top prospects are years from the big leagues.

Law's 2017 Prospect Ranks

ESPN

Farm System Rankings:

• Nos. 30-21

• Nos. 20-11

• Nos. 10-1

Prospects:

• Nos. 100-81

• Nos. 80-61

• Nos. 60-41

• Nos. 40-21

• Nos. 20-1

• Prospects who missed

• Top 100 table

Prospects by team:

AL East

• Orioles | Red Sox | Yankees | Rays | Blue Jays

NL East

• Braves | Marlins | Mets | Phillies | Nationals

AL Central

• White Sox | Indians | Tigers | Royals | Twins

NL Central

• Cubs | Reds | Brewers | Pirates | Cardinals

AL West

• A's | Angels | Astros | Mariners | Rangers

NL West

• Diamondbacks | Rockies | Dodgers | Padres | Giants

Feb. 2: Top prospects by position

Feb. 3: Sleepers

• Law's 2017 rankings

• Law's 2016 rankings