Six reasons why Man Utd are struggling to score goals: Marcus Rashford toiling in the middle, injured star signing and a draining U.S. tour

United's top target for the summer was a striker, and Rasmus Hojlund was ultimately the man they chose to lead their attack for the next few years, opting to sign the 20-year-old for £72 million ($92m) from Atalanta rather than spend even more on Harry Kane.

However, United's great striking hope arrived with a back injury and is still waiting to make his debut. Hojlund is 6'2 in height and blessed with explosive pace and power, which will make him an asset once he recovers, potentially in time for the trip to Arsenal on September 3.

United spent most of last season without a proper striker due to Anthony Martial's fitness troubles, Cristiano Ronaldo's problems and eventual departure, and Wout Weghorst's lack of ability. Indeed, the Dutchman was often deployed as a No.10 rather than a No.9. So it is not wholly surprising that United should be haunted by the same problems up front as last season until Hojlund makes his long-awaited debut.

Another consequence of Hojlund being injured means that Marcus Rashford has had to deputise at centre-forward. Last season was the most prolific of Rashford's career, but his best moments came when coming in off either wing, such as when he terrorised Barcelona at Camp Nou or scored after a sensational slalom run from beyond the halfway life against Burnley.

Rashford admitted to Gary Neville on The Overlap over the summer that his favourite position is on the left of the attack as he can get more involved in the game. He said: "Left is easier to stay in the game, and from when I was young I've always wanted to be involved in the game. That's why I struggle playing centre-forward sometimes because of my patience. You might not touch the ball for 20 minutes, and then your first touch might be an opportunity to score. You have to be mentally switched on. Whereas on the left. it's more natural, feels more normal."

Rashford has had to led the line in the first two matches and he has not looked his usual self. He had four shots against Wolves, but three of them were blocked. He had three opportunities against Spurs, one of which was blocked, one saved by Guglielmo Vicario and the other, a free header after a rabona cross from Bruno Fernandes, sailed over the bar.

When he was substituted, he was seen sulking on the bench. The striker who scored 30 goals last season has a total of two shots on target so far this campaign, and Hojlund's return cannot come soon enough for him either.

United have always been renowned for their exciting wing play, but their wide players have struggled to get going, while Rashford playing centrally is only part of the problem. Antony still has a lot to prove after an underwhelming debut season in which he scored only four Premier League goals and provided just two assists, as many as in the Eredivisie with Ajax. His £85m ($107m) price tag adds yet more pressure on him and he is not even coming close to justifying the fee United paid for him.

Antony has not made a strong start to this campaign, hammering the post with a good opportunity against Spurs and creating little of note against Wolves. Alejandro Garnacho, who lit up last season, has also been disappointing, and only added weight to the argument that he is far more effective as a substitute than in the starting XI.

Jadon Sancho deserves to start in place of Garnacho against Forest after being benched for the first two games, but he has looked shorn of confidence and spark in most of his appearances since his move from Borussia Dortmund, also failing to live up to his own £74m ($93m) transfer fee.

While United have hardly played well in their opening two games, they have at least created chances, indicating that the reason they have scored so few goals is more down to an inability to finish off moves than craft them. Against Tottenham, they had 14 shots in the first half, more than in any away game since they took on Blackburn Rovers in October 2008, when they were defending Premier League and European champions.

Rashford and Antony spurned good opportunities in north London, but the clearest fell to Fernandes, who headed over the bar after a dream cross from Luke Shaw. After the Tottenham game, Ten Hag emphasised how important it is to score the first goal in the Premier League.

Making promising starts but failing to take their chances and then losing was a familiar theme last season, with United paying a high price for their profligacy against West Ham and Brighton, in particular. They are bound to create opportunities against Forest; they need to take them.

Ten Hag's first piece of business was signing Mason Mount, a move which baffled more than a few supporters and observers, but which the Dutchman insisted would make United far more dynamic. Mount has struggled to settle in and will now not be available until at least after the September international break due to a hamstring injury.

Mount did not impress during pre-season and has found the competitive games even more difficult. He has been playing in a deeper role than he was used to at Chelsea, sitting alongside Fernandes. The position has had the twin effect of making United more vulnerable defensively as Casemiro has looked isolated and made them more blunt in attack.

The England midfielder had only 26 touches against Spurs, the 10th lowest amount of the 11 United players who started. He also failed to have a single touch in the opposing area.

Another point of concern from United's first two games is how tired some of the players look. The Red Devils played 62 matches last season and more than a few squad members looked on their last legs by June. Some players, in particular Casemiro, now look in a similarly bedraggled state after just two matches.

United did not help themselves by organising a gruelling pre-season campaign, playing eight friendlies in the space of 25 days across five countries. The bulk of their preparations took place in the United States, where they criss-crossed the country, visiting four different states, racking up more than 5,700 air miles in total. They travelled from New Jersey to San Diego, then to Houston before finishing up in Las Vegas.

While these tours have huge commercial value to United, the primary objective of a pre-season campaign is to prepare the players for competitive matches, and the tour seems to have had the opposite effect.

"It’s been good but there’s been a lot of games and too much travelling," said Christian Eriksen after the defeat to Borussia Dortmund in Las Vegas. "We expected a tough pre-season, but there’s probably been too much travelling around. Playing in different places has to happen and we’ve adapted, but everyone is happy to go home."