One of the main talking points to come out of Arsenal’s disappointing draw against Slavia Prague was the performance of Thomas Partey.
Given Partey’s pedigree and the vast experience he has accrued while playing in top-level European ties with Diego Simeone's Atletico Madrid, Thursday night’s crucial encounter was precisely the type of game he was signed to make a difference in.
However, he instead struggled badly and didn’t even complete the 90 minutes, with Mikel Arteta bringing him off just over 10 minutes from time, replacing him with Mohamed Elneny.
The sight of the Ghana international watching the closing stages of the biggest game of the season from the bench was one few could have envisaged when he joined amid much fanfare on the final day of last summer’s transfer window .
So, what is going on with Partey? Why has he so far struggled to make the sort of impact in north London that so many were expecting?
“The biggest difficulty he has had is that he has not been fit,” Arteta told reporters ahead of Sunday’s Premier League trip to Sheffield United. Then, every time he was fit he missed the next game and was out [again].
"For a long time, physically, he has not had time to prepare himself to play at the highest level. Obviously, that has an impact because the level in the Premier League is high and how fit you are is key.
“He has not been in a position to be able to perform at the level he can. Up to this point, he has not had that possibility.”
There’s no doubt Partey’s time at Arsenal so far has been disrupted massively by injuries.
After arriving on the final day of the window, he made his debut as a late substitute against Manchester City in October before impressing in his first start away from home, at Rapid Vienna in the Europa League.
The difference he was going to make to Arteta’s team was already abundantly clear and that was demonstrated again in impressive fashion when he produced a midfield masterclass in the 1-0 win at Manchester United in November .
"He was outstanding,” former United captain Roy Keane said after the game. “When you watch a player live, that's when you can judge them and the more I look at him, the more I wish he was in the United midfield.
“He's big, strong and aggressive – and he can pass it forward. He can deal with the ball.
"I had my battles with [Patrick] Vieira and I think this kid has got a chance of matching what Patrick used to do."
At that point, it looked like Partey would go to become the dominant force in Arsenal’s midfield, the kind of transformative presence that the team had been lacking for years.
But the thigh injury he sustained against Aston Villa the following week halted him in his tracks.
Although he returned a month later, the 27-year-old didn’t even make it to half-time against Tottenham in his first game back before a recurrence of the injury forced him off and left him facing another four-week spell in the treatment room.
Partey has been playing catch up ever since, with another injury – this time due to a hamstring problem – also forcing him to sit out the majority of February.
“It is very difficult to make a real assessment because he has missed six months,” said Arteta. “That is a long time.
“He is still adapting to our way of playing which is different to what he did at Atletico Madrid.
“He has had some big sparks and we can all see what he can bring to the team.
“Now it is about finding that consistency level that we need from him and building a team that can play around him because he has that capacity.”
Partey was brought in to take Arsenal up a level and although he has yet to show what he can do on a consistent basis, the type of performance he produced in the win at Old Trafford was a clear indication of what he can do.
There is no major worry at the club over his recent showings, with Thursday night’s disappointing display viewed more as a one-off than a cause for concern .
There is an understanding that he needs time to settle into his new surroundings and that it has not been easy for him to make the move to England in the middle of a pandemic.
The midfielder has had to deal with house hunting in recent months and although he has now bought his own place, he is living alone, with no members of his family having yet joined him in London.
“People have their own opinion,” the midfielder said last month when assessing his own form since his move to Arsenal. “But it depends on me and how I adapt to the situation that I’m in.
“I have had a few games, against Man United and against Wolves [where I was 100 per cent], and I was able to show what I can do.
“This is just the start. I’m starting to get used to how my team-mates play, how the Premier League goes and, with time, everything will be good.”
Partey’s disappointing showing against Slavia Prague was one of a player who has clearly had his confidence dented in recent weeks.
He had just 53 touches – way down from 81 he usually averages per 90 minutes this season. And when he did get on the ball, he was unusually sloppy.
Of his 41 passes – a number that again is way down on his average of 65 – just 80.5% were successful. That’s drastically lower than his 87.4% average for the season so far.
Partey also attempted fewer dribbles than his usual average, made fewer passes into the box and made fewer tackles.
There is no doubt it was a performance that was well below par for a player of his quality, but it’s not one that has left Arteta at all concerned, with the Arsenal boss predicting that "the best version of Thomas" will be on show during the final weeks of the campaign.
That is something Arsenal have not seen enough of since the midfielder arrived and the performance in the first leg against Prague was nowhere near the standard that he can produce.
But he’s already shown the difference he can make when he does click into gear and if Partey gets things right in the Czech Republic next week, then Arsenal will certainly fancy their chances of booking their spot in the Europa League semi-finals.