Casemiro: Man Utd midfielder showing signs of decline as poor form creates a conundrum for Erik ten Hag

The international break was mercifully-timed for Casemiro. Having been sent off in Manchester United's Champions League loss to Galatasaray and hooked at half-time against Brentford, the Brazilian looked like a player in need of some time away.

Not that Brazil's fixtures brought him much relief. The 31-year-old had to be substituted after picking up a knock in their 1-1 draw with Venezuela and, having returned to face Uruguay a few days later, he was powerless to prevent a 2-0 defeat. He can't catch a break.

It has been a similar story all season. Casemiro excelled in his first campaign at Old Trafford, the five-time European champion credited with instilling a winning mentality as he inspired Manchester United to their first trophy in six years in the form of the Carabao Cup.

But the subsequent decline has set alarm bells ringing. In their opening game against Wolves, one they were fortunate to win, Sky Sports pundit Gary Neville described Casemiro being "torn to shreds" as part of a "non-existent" midfield.

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That performance set the tone.

Casemiro, previously imperious in front of Manchester United's defence, now looks sluggish and vulnerable, the situation hitting a nadir with his early withdrawal for Christian Eriksen against Brentford after an error-strewn first-half display. "I wanted more football," said Erik ten Hag afterwards.

The explanation felt brutal and added to a growing sense of unease around the midfielder. The decision to pay £70m for a 30-year-old on a lucrative long-term deal looks increasingly questionable.

Casemiro has of course contributed goals, scoring four to add to the seven he scored last term, but he is in the team primarily to protect and spoil and the numbers show a significant drop-off.

Casemiro, whose defensive diligence and outstanding awareness provided the platform for so much success at Real Madrid, is making significantly fewer tackles and interceptions than last season.

He is not winning as many duels nor regaining possession with anything like the same frequency.

Opponents are bypassing him with worrying regularity.

In fact, among all Premier League players since the start of last season, only Fulham's Joao Palhinha and Brentford's Mathias Jensen have been dribbled past more times than Casemiro on 64.

Manchester United's opponents are profiting from their openness.

With Casemiro labouring centrally, Ten Hag's side are conceding more goals, giving up more shots and allowing teams to progress further upfield against them. They have already conceded three or more times on four separate occasions this season. They sit 10th in the Premier League and bottom of their Champions League group.

There are some mitigating circumstances. Casemiro has not been helped by upheaval around him. United have been hit by widespread injury problems. Ten Hag has used six different midfield combinations in only 11 games, with Casemiro the only constant.

Sky Sports pundit Jamie Carragher outlined their lack of balance in that part of the pitch on Monday Night Football in August. "This guy in midfield," he said of Casemiro, "is being left exposed on his own in the middle of the pitch and he cannot cope."

But the worry is that, even when Ten Hag has sought to address that imbalance, sacrificing an offensive midfielder for a more defensively-minded one, Casemiro has continued to struggle.

Against Brentford, for example, he had Sofyan Ambrabat alongside him at the base of midfield and yet delivered a performance so bad Ten Hag was forced to cut it short at the halfway point.

There are stylistic issues affecting Casemiro too.

Ten Hag's team is now set up to press higher and more aggressively. They rank top for high turnovers and second for pressed sequences this season. Their start distance is the highest in the division, underlining the extent to which they have pushed upfield.

The manager's determination to win possession as high up as possible inevitably means committing more bodies forward and that in turn has left Casemiro with more ground to cover.

It is hardly surprising that a player who averages fewer sprints than anyone else at United is struggling to meet those increased physical demands and the numbers paint a troubling picture in the context of his age.

Casemiro turns 32 in February. He already has more than 600 games under his belt for club and country. It is only natural, then, that such a heavy workload might be starting to take a toll.

Those concerns become more acute when comparing Casemiro's output to the No 6s playing for United's big-six rivals this season. He fares poorest in a host of key off and on-the-ball metrics.

Indeed, his defensive drop-off is only one side of it.

While others, such as Declan Rice, Rodri and Moises Caicedo, are giving their teams control in possession, Casemiro is doing the opposite, losing the ball roughly 14 times per 90 minutes, with a passing accuracy rate far lower than those of his contemporaries.

The numbers may be impacted by Casemiro's tendency to attempt more ambitious passes, but when Ten Hag says he "wants more football", he leaves no room for doubt that he sees the problem.

So what next? Casemiro has been ruled out of Saturday's meeting with Sheffield United, instructed by the club to stay in Brazil and recover from the small issue picked up in their game against Venezuela. But what happens after that will be telling.

Will Ten Hag persist with him and give him a chance to prove the sceptics wrong? Or will he do as he did against Brentford and take him out of the team?

With three years left to run on the huge contract he signed last summer, there is no easy answer. Casemiro, a transformative signing in the short-term, is becoming a longer-term conundrum.

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