United are 12th after the 1-1 draw at Fulham which leaves them with just 5 points after 5 games under manager Michael Carrick who is under increasing pressure to turn the side around as soon as possible.
As well as their poor form in the Premier League, United also went out of the EFL Cup after throwing away a 2-0 lead to lose 3-2 to Brighton, which leaves the side with just 3 competitions to play for.
Their dire domestic form was countered with a 4-0 win over Sabah earlier this month, a game United were firm favourites to win.
Speaking to talkSPORT Bet, McCoist stated that European football cannot be United's excuse this season as the club continues to falter under Carrick's guidance.
"Fulham have improved, to be honest, and were much better at Liverpool last week. But when I look at United, if they concede first, I don't know if there's enough belief or spirit to come back. If Fernandes doesn't play well, they don't have much else to grab a game by the scruff of the neck.
"Being 2–0 up against Brighton and losing is the first time they've lost a lead like that at halftime at Old Trafford in 50 years, it's a ridiculous statistic going back to 1984. I was at the Hull game where Hull thoroughly deserved to beat them.
"They beat Ipswich, but then conceded a 96th-minute goal to Maitland-Niles against Everton. It just seems to be one problem after another at United. I thought they would have started better.
"I expected them to struggle to a degree with European football this year, but that hasn't even started yet and they already have problems. They can't use European football as an excuse like last year when they only played 40 games.
"So it's a real concern that Michael Carrick's side haven't started well. I thought European football would eventually catch up with them, but they haven't performed well enough for that to even be the factor."
He also stated "Manchester United don't have the same pull for players as they once did, and I stand by that. Do people still want to go there? Of course. But if you're elite tier now, you're looking at Manchester City, Arsenal, or Liverpool."
The Red Devils face Tottenham after the international break, and a loss could send Carrick packing, a decision that may cost the side around £8M according to reports.