The two teams meet for the first time since March when they played out a 1-1 draw at the Gtech Community Stadium, where Mason Mount's 96th-minute strike was cancelled out in dramatic fashion by a 99th-minute Kristoffer Ajer equaliser.
Match preview
Not for the first time, Erik ten Hag has survived the axe and lives to fight another day as Man United manager, despite overseeing the club's worst-ever start to a Premier League season, with only eight points accumulated and two wins posted in their opening seven matches.
The Red Devils have opted to remain silent on Ten Hag's future following a seven-hour executive meeting that was held in London just over a week ago by members of the club's leadership group, including Sir Jim Ratcliffe and Joel Glazer.
Nevertheless, the spotlight remains fixed on Ten Hag at present and the Dutchman is tasked with turning the club's fortunes around quickly, as they currently sit 14th in the Premier League table, closer to the relegation zone than the top four, while they are already 10 points adrift of league leaders Liverpool.
Since thrashing Barnsley 7-0 in the EFL Cup in mid-September, Man United have failed to win any of their last five matches in all competitions, drawing four including a goalless stalemate at Aston Villa prior to the international break.
Man United have had little to celebrate at Old Trafford so far this term, but there is reason to be optimistic ahead of Saturday's fixture, as they have won each of their last five home league games against Brentford by an aggregate score of 13-2 - not since 1937 have they lost at home to the Bees.
Brentford buzzing out of the blocks has become the new norm in the Premier League, with Thomas Frank's side having scored the opening goal inside the first 80 seconds in each of their last four matches.
The Bees failed to beat Manchester City, Tottenham Hotspur or West Ham United when netting the opener, but they came out on top by a thrilling 5-3 scoreline at home against basement club Wolverhampton Wanderers before the international break.
Frank's side have picked up all 10 of their Premier League points this season on home soil and currently sit 11th in the table, two points ahead of Saturday's opponents Man United and three points behind the top four.
Brentford have suffered defeat in each of their first three top-flight away matches this term, albeit against Liverpool, Man City and Spurs, and they head to Old Trafford this weekend seeking to avoid losing their opening four league games on the road for the first time since 1961-62 when they lost their first nine as a third-tier club.
The Bees' record against Man United does not bode well ahead of Saturday's clash, as they have only won one of their last 10 encounters with the Red Devils in all competitions, losing seven and conceding 24 goals, but Frank's fearless side will nevertheless fancy their chances against a Ten Hag team struggling for form.
Manchester United Premier League form:
L
L
W
D
L
D
Manchester United form (all competitions):
W
D
D
L
D
D
Brentford Premier League form:
L
W
L
L
D
W
Brentford form (all competitions):
W
L
W
L
D
W
Team News
Man United are facing an injury crisis as they could be without as many as 10 first-team players; Leny Yoro (foot), Tyrell Malacia (knee) and Harry Maguire (muscle) are all sidelined and Noussair Mazraoui is also set to miss out after he recently underwent an operation to address heart palpitations.
Manuel Ugarte limped off with an unspecified issue on international duty with Uruguay on Tuesday and he is set to be assessed along with injury-riddled Luke Shaw (calf), Mason Mount (knock), Kobbie Mainoo (hamstring), Alejandro Garnacho (knee) and Amad Diallo (illness).
There have been reports suggesting that Ten Hag could use Jonny Evans at left-back, with Diogo Dalot moving over to the right side of a back four, while Matthijs de Ligt and Lisandro Martinez could both be recalled to start at centre-back.
Casemiro, Christian Eriksen and Bruno Fernandes are all in contention to start in midfield, while Rasmus Hojlund, who played for just under an hour for Denmark on Tuesday, is set to battle with Joshua Zirkzee for a start up front.
As for Brentford, they are still having to cope without Yoane Wissa (ankle), Rico Henry, Josh Dasilva, Igor Thiago (all knee), Aaron Hickey (thigh) and Gustavo Nunes (back) due to injury.
Mikkel Damsgaard (knock), Christian Norgaard (muscle) and Mathias Jensen (calf) were all unable to represent Denmark during this month's international break and the midfield duo are doubts ahead of this weekend's contest.
Frank may consider reverting to a three-at-the-back system against Man United, with Sepp van den Berg, Ethan Pinnock and Nathan Collins all starting in central defence, while Kristoffer Ajer and Keane Lewis-Potter operates as wing-backs.
Bryan Mbeumo is Brentford's top scorer so far this season with six goals in seven Premier League games, including three in his last three, and he is set to continue in attack alongside either Kevin Schade or Fabio Carvalho.
Manchester United possible starting lineup:
Onana; Dalot, De Ligt, Martinez, Evans; Eriksen, Casemiro; Garnacho, Fernandes, Rashford; Zirkzee
Brentford possible starting lineup:
Flekken; Van den Berg, Collins, Pinnock; Ajer, Jensen, Norgaard, Janelt, Lewis-Potter; Schade, Mbeumo
We say: Manchester United 2-2 Brentford
While Brentford can travel to Old Trafford without any pressure on their shoulders, that cannot be said for Ten Hag who can ill-afford to see his Man United side produce another below-par performance on home soil, where they have lost their last two league games by a 3-0 scoreline.
Both teams - who will not be at full strength on Saturday - have looked vulnerable in defence this season and goals are to be expected here, but it is difficult to confidently predict a winner on this occasion, so an entertaining score draw could be on the cards.