With United 3-1 up against Newcastle United, Shoretire – who signed his first professional deal with the club after turning 17 earlier this month – came off the bench with two minutes remaining.
Shoretire replaced Rashford, and the latter – who scored and won a penalty to help United claim victory – had warm words for a fellow United academy graduate.
Rashford tweeted a photo of Shoretire replacing him as a late substitute with the message: “Cherish this moment for ever little bro. Your family must be very proud.”
Shoretire is highly rated by United staff, and has been in sparkling form to earn a promotion to the first team despite only recently turning 17.
The youngster scored a fine hat-trick for the Under-23s in a recent 6-4 win over Blackburn, and has been handed the number 74 shirt by Ole Gunnar Solskjaer.
Shoretire was originally involved in the Manchester City academy before switching to United aged 10, and has been capped at England U16 level.
The winger could get more minutes during the second leg of United’s Europa League round-of-32 tie against Real Sociedad, with the Red Devils 4-0 up on aggregate.