The Englishman, who scored against Real Madrid last weekend, begun the game on the left hand side and, aside from a fizzed shot that skimmed over the bar, struggled to make an impact on Ernesto Valverde’s side.
He was then replaced by Andreas Pereira in the second half after going down and showing signs of discomfort.
But Mourinho, speaking after the game, made it clear that the 24-year-old hadn’t suffered an injury, pointing towards simple muscle tiredness as the reason instead.
“No, no problem with Jesse,” he said.
“I think it’s just muscle tiredness.”
Praising Lingard can often feel like a taboo practice amongst Man United fans, kind of like advocating abortion in the Deep South, but nobody should question the winger’s work rate.
Regardless of context, Lingard runs himself into the ground each game, tearing across the surface in an attempt to hassle the opponent. This is the primary reason why both Louis van Gaal and Mourinho have opted for using him; both managers appreciate that disciplined sort of work rate.
But in the humid Washington night, with United receiving a footballing lesson from the Catalans, Lingard was feeling it after the hour mark. Teams of Barcelona’s quality can rip your soul out, which is, funnily enough, exactly what you need in pre-season, as Mourinho noted after the game.