With Friday's MLB trade deadline fast approaching, rebuilding clubs are scouring the minor league teams of contenders in hopes of bolstering their farm systems with blockbuster packages of prospects.
The Chicago Cubs showed how highly a contender can value what it views as the missing piece when they shipped highly regarded shortstop prospect Gleyber Torres to the New York Yankees for two months of Aroldis Chapman in 2016.
However, there are some prospects who are simply untouchable in trade talks.
Ahead we've highlighted seven top-tier prospects on contending teams who won't be going anywhere this summer, as they are too important to their organizations' long-term plans and have too much upside.
CF Garrett Mitchell, Milwaukee Brewers
B/R Top 100 Prospect Rank: 59
Slowly but surely, the Milwaukee Brewers are restocking a farm system that had thinned considerably in recent years.
When UCLA standout Garrett Mitchell fell into their laps at No. 20 in the 2020 draft, he immediately became the No. 1 prospect in the system, and he is off to an excellent start in his pro debut.
The 22-year-old hit an absurd .359/.504/.620 with 12 extra-base hits and 12 steals in 28 games at High-A Wisconsin to earn a promotion to Double-A Biloxi.
Questions about his ability to hit for power were part of the reason he slipped in the draft, but even if he maxes out at 15 homers, his polished approach and defensive profile in center field give him an extremely high floor.
The National League Central-leading Brewers will be buyers, but don't expect Mitchell to be included in any potential deals.
C Tyler Soderstrom, Oakland Athletics
B/R Top 100 Prospect Rank: 41
The Oakland Athletics paid a steep price to sign Tyler Soderstrom as the No. 26 pick in the 2020 draft, inking him to a $3.3 million bonus that was $650,000 above slot value.
It already looks like a wise investment.
The 19-year-old was billed as one of the best pure hitters in the class, and he is living up to the hype with a .306/.390/.568 line that includes 20 doubles, 12 home runs and 49 RBI in 57 games at Single-A Stockton.
While he has the defensive tools to stick behind the plate, he is also athletic enough to handle another position if the Athletics want to expedite his bat to the majors.
The A's are in the thick of the American League West race, and they could use some bullpen help and an upgrade at second base, but the cost-conscious organization can't afford to mortgage a potential homegrown star for a short-term upgrade.
1B Triston Casas, Boston Red Sox
B/R Top 100 Prospect Rank: 36
Triston Casas climbed to the top of the Boston Red Sox farm system when he hit .256/.350/.480 with 26 doubles, 20 home runs and 81 RBI in 120 games in Single-A and High-A at the age of 19 in 2019.
Now he's suiting up for Team USA in the Olympics after hitting .271/.354/.424 with 12 extra-base hits in 46 games at Double-A Portland to start the year.
The 21-year-old is the future for the Sox at first base, and he is just scratching the surface of his 65-grade power.
It would also take a blockbuster addition to pry middle infielder Jeter Downs loose, but Boston might be slightly more inclined to part with him after selecting prep shortstop Marcelo Mayer with the No. 4 pick in this year's draft.
The Red Sox have traded top-tier prospects in recent years—Yoan Moncada, Michael Kopech, Manuel Margot and Anderson Espinoza—but don't expect Casas to be dealt any time soon.