With Tuesday's non-waiver Trade Deadline inching closer and closer, front offices around the American League West will be tasked with evaluating their internal assets to determine which players they'd be willing to part with to better position their clubs for the future. But nearly every team has one player who is so invaluable that he warrants the coveted "untouchable" label.
Here's a look at the division's most untouchable players -- and several who you may be surprised to hear aren't necessarily off the table in trade talks.
Angels
Who it is:Michael Trout
Why: Trout is widely considered the best player in baseball, is under team control through 2020 and is in the middle of his prime at age 26. He's the face of the franchise and the best building block the Angels could ask for as they look to win their first postseason game since 2009.
Who it isn't:Justin Anderson
Why not: Anderson rose from relative obscurity to earn a spot in the back end of the Angels' bullpen this season and has shown flashes of dominance, mixing an upper-90s fastball and a nasty slider. He's only 25 years old and is under team control for six more seasons, but relievers are notoriously volatile, which could prompt the Angels to entertain offers for him.

Astros
Who it is: Kyle Tucker
Why: The 21-year-old outfield prospect is getting his feet wet in the Major Leagues and is the youngest player in the AL. The Astros rebuffed any team asking about him in the past couple of years and believe he will be a cornerstone player on their club for the long term.

Who it isn't: David Paulino
Why not: The big right-hander still shows up on prospect lists, but is 24 years old, was suspended 80 games last year for a performance-enhancing substance violation and hasn't pitched well in the big leagues. He was in the rotation at Triple-A Fresno, but is currently in the Gulf Coast League -- far away from Houston.
Athletics
Who it is: Matt Chapman
Why: Consider Chapman the poster boy for a burgeoning A's club brimming with young talent -- a group the front office wants to keep together for several years to come. The A's already dealt away one star third baseman -- remember Josh Donaldson? This time, Oakland's star defender is staying put.
Who it isn't: Blake Treinen
Why not: Treinen has been an absolute godsend for these A's, who have no plans of trading him. That doesn't mean they won't be tempted, and a premier package from a desperate contender seeking relief help just might change their minds. They already have something of a Treinen clone in their bullpen, anyway, in Lou Trivino, plus another experienced closer, Jeurys Familia.

Mariners
Who it is: Edwin Diaz
Why: The 24-year-old closer has been a difference maker for a team that has put itself in prime postseason contention by winning close games this year. Diaz has emerged as one of the game's elite closers with his upper-90s heat and wipeout slider. The Mariners aren't about to part with such a shutdown reliever who is making just $545,000 this year, isn't arbitration eligible until 2020 and won't be a free agent until 2023.

Who it isn't: Ryon Healy
Why not: Though the 26-year-old first baseman has shown good power with 45 homers in the past year and a half with the A's and Mariners, he has just a .292 on-base percentage in that span and could soon be a man without a position once Robinson Cano returns on Aug. 14 from his 80-game suspension. With Dee Gordon now entrenched at second, Cano can play first and that cuts down on Healy's role both this year and potentially beyond. Like Diaz, Healy is a minimum salary player with four more years of club control, which could make him an attractive trade chip for a team betting on his upside.
Rangers
Who it is: Nomar Mazara
Why: The Rangers are building around young players, and Mazara, in his third year in the big leagues, has established himself as a force in the middle of the lineup. He was leading the Rangers in RBIs before going on the disabled list with a sprained right thumb. Mazara is one of the critical foundation pieces for the Rangers' future.

Who it isn't: Keone Kela
Why not: Kela has done an outstanding job as the Rangers closer, so it would seem strange that a team that needs young pitching would trade him. But the Rangers need starting pitching more than anything and Kela could be their most coveted player given the number of teams looking for relievers. The Rangers also have another potential young closer in Jose Leclerc. The Rangers could talk about Kela if it gets them frontline starting pitching in return.