It made sense for the New York Yankees to trade away TJ Rumfield.
That doesn’t mean it worked out well for the Yanks. Rumfield had a breakout season in 2026 for the Colorado Rockies.
And by the time the year was over, Rumfield had achieved quite the feat: He led the National League in on-base percentage.
He did that as a rookie, too, which almost never happens.
TJ Rumfield MLB History
Rumfield is the first rookie to lead his league in on-base percentage since 1926.
It’s been 100 years since the man known as Walter “Cuckoo” Christensen achieved the feat, according to Patrick Lyons.
This is an achievement that was also achieved by Shoeless Joe Jackson.
Rumfield apparently needs to get a cool nickname.
#Rockies TJ Rumfield is the first rookie in 100 years since Walter “Cuckoo” Christensen in 1926 to lead his league in OBP.
Rumfield’s .390 OBP is tops in the National League.
You may have heard of the first rookie to ever accomplish that: Shoeless Joe Jackson (1911).
— Patrick Lyons (@PatrickDLyons) September 27, 2026
If Rumfield had stayed with the Yankees, he likely wouldn’t have even had an opportunity to do this.
But with the Rockies, Rumfield became an under-the-radar star.
He ended the year hitting an even .300 with 16 home runs, 73 RBI and an .843 OPS.
The 6-foot-5, 238-pound, 26-year old first baseman has a bright future ahead in Colorado.
Why Did Yankees Trade TJ Rumfield?
The simple explanation is that Ben Rice had already broken out.
If Rice hadn’t put together a big 2025 season, maybe the Yanks consider Rumfield at first base. But Rice did break out. He’s a star.
Rumfield hit .285 with an .825 OPS in Triple-A with Scranton/Wilkes-Barre in 2025, so he had certainly done his part to get noticed.
As it turns out, it was just the Rockies who noticed a chance to snag a promising player from an organization that didn’t have an easy path toward using him.
The Yankees traded Rumfield to the Rockies for relief pitcher Angel Chivilli.
“It’s one of those things where you’re sitting there and you could have a good year,” Rumfield said, via The Athletic, “but Ben Rice is spectacular. He’s a great player. A great hitter. A great person. We play the same position. It’s hard to be on the same roster together.”
TJ Rumfield Got Better With Yankees
The Athletic’s Brendan Kuty wrote this about Rumfield’s time in the Yankees’ system:
“Rumfield credited several people from his time with the Yankees organization for his success, including player development leader Kevin Reese and former minor-league hitting coordinator Joe Migliaccio, who is now with the Miami Marlins. Rumfield also shouted out current Yankees coaches Dan Fiorito (first base), Ryan Hunt (director of infield, outfield, base running) and Jake Hirst (assistant hitting coach).”
It’s been quite the journey to this point. He was a 12th-round pick by the Phillies in 2021 out of Virginia Tech.
The Yankees got him in a trade in Nov. 2021 with Joel Valdez for Nick Nelson and Donny Sands — three guys who haven’t made any inroads, and then the rising star Rumfield.
And then the Yanks sent Rumfield to the Rockies, where he has become a quality big leaguer in a hurry.
Yankees Traded TJ Rumfield To Rockies — And He Matched 1926 MLB Record