The Blues midfielder was part of a strong squad which left London for America just hours after the end of the Premier League season on Sunday.
Maurizio Sarri started a strong line-up against New England, with Eden Hazard, David Luiz and Kepa Arrizabalaga all starting.
Chelsea are currently preparing for the Europa League final against Arsenal on May 29 and Sarri was unhappy about having to travel to the United States given the long and tiring campaign his players have had.
But due to prior commitments, they were made to travel, and in doing so they raised an incredible $4million (£3.1m) for anti-antisemitism charities.
The Blues took a commanding 2-0 lead into the break, but the afternoon took on a sourer note for the visitors in the second half as Loftus-Cheek limped off with an injury.
The midfielder went down with 20 minutes remaining in the game, and was visibly uncomfortable as he was helped off.
He appeared to hurt his heel, with fans taking to Twitter and immediately fearing the worst for their star.
“Loftus Cheek tore his Achilles. He’ll be back in like 7-8 months. F**k you Chelsea board and your stupid friendly games,” one fan raged.
“Loftus-Cheek tore his Achilles, probably. Thanks to you idiots at Chelsea board,” another wrote.
“So… Loftus-Cheek definitely just tore his Achilles as well,” one fan fumed.
Another posted: “And you knew it would happen! Loftus-Cheek one of six half time subs looks like a serious Achilles/ankle injury. Just brilliant planning for this game Chelsea.”
Some fans chose to blame Sarri for the injury, despite the Italian boss venting his frustrations over having to play the game at all.
“Wait Sarri played first teamers in a meaningless friendly, and now Loftus Cheek is injured,” one fan tweeted.
“And what should happen, just happened, Ruben Loftus-Cheek looks injured. F**k off Chelsea and Sarri for your stupid friendly games,” another posted.
One fan raged: “And we just lost RLC for the Europa League final f**k you Sarri.”
“He doesn’t give a flying f**k about this club, and you’re deciding yourself if you think it will all magically change next season. A FRIENDLY. Not one youth player gets a full debut. #SarriOut,” another posted.