The hosts will be aiming to bounce back in this fixture after a surprise 4-2 defeat to Queens Park Rangers on Saturday, in which the west London side took advantage of a number of half-time changes to score three in quick succession before the hour mark.
In the club's first two friendlies against Derby County and QPR, manager Ole Gunnar Solskjær has deployed a mix of first team, reserve, and academy players and he will likely follow suit against Brentford.
The Bees themselves are currently unbeaten in pre-season having defeated AFC Wimbledon (0-1), Boreham Wood (0-2), and Watford (1-3), with the latter being held behind closed doors at Watford's training ground.
Thomas Frank reverted to a 3-4-3 set-up at the weekend and trialled Kristoffer Ajer on the right of the back three. Fellow new signings Frank Onyeka and Myles Peart-Harris have been training with the squad at St. George's Park and could also be in contention to play.
United are undefeated in their last five fixtures against the newly-promoted team, with meetings dating back to the 1930s and 1940s when the Hounslow-based club was last in the top-flight.
Manchester United will be without Eric Bailly and Amad Diallo as they compete for Ivory Coast at the Tokyo Olympics.
Solskjær will also be missing Marcus Rashford, Harry Maguire, Luke Shaw, and new signing, Jadon Sancho, as they rest after helping England reach the Euro 2020 final. David de Gea is also unavailable due to Spain reaching the semi-finals.
Brentford have no new absentees. Christian Nørgaard, Mathias Jensen, and Pontus Jansson are yet to return to training following the Euros, while Josh Dasilva remains sidelined with a hip injury.
Frank could give unofficial debuts to Frank Onyeka and Myles Peart-Harris, while Kristoffer Ajer could make his first public appearance in a Brentford kit after playing 45 minutes against Watford.
Manchester United: Heaton; Wan-Bissaka, Tuanzebe, Mengi, Williams; Garner, Matić; Pellistri, Lingard, James; Greenwood.
Brentford: Raya; Ajer, Goode, Pinnock; Stevens, Onyeka, Janelt, Thompson; Fosu, Toney, Ghoddos.
Ones to watch
Jesse Lingard endured a career-revitalising loan stint at West Ham United last season, contributing nine goals and five assists in 16 Premier League appearances, and will be keen to make an impact during pre-season, adding to his goal scored against QPR.
After a scoring a record-breaking 31 goals in the 2020/21 regular Championship season, Ivan Toney has picked up from where he left off last campaign with three goals in as many pre-season games, including a brace versus Watford at the weekend.
Where to watch on TV
This fixture will kick-off on Wednesday 28 July at 8pm GMT and will be broadcast on MUTV.