It took just 22 seconds for Diogo Jota to prove his worth against Nottingham Forest midweek, with the Portugal striker rising highest to head home Kostas Tsimikas' corner kick. With one touch, he showed why he is the number one pick through the center.

Two days later, however, he was spotted training on his own in Kirkby. And on Friday, Arne Slot confirmed that Jota is a doubt for the trip to Brentford this weekend because of a minor injury setback.

"There is no doubt about his importance for us but he wasn't training, so we have to see today where he is," Slot said during his press conference. "It's not sure he is available tomorrow, we'll see today.

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"He felt a little bit when he came in, a niggle during the half-hour he came in. He finished the game but complained a bit about it. We'll see for tomorrow."

Jota has started just twice since being out for 12 games — against Tottenham and Accrington — and has had to settle for being a substitute in seven other fixtures. Now, he could miss out altogether in West London, with Lille then to come in the Champions League on Tuesday.

"Not because it's Jota but every player has their own program, 80 or 90 per cent is the same but every player has stuff they want to improve or to prevent a certain injury," Slot explained. "So that is the same for all players, so there is a special program for every single player."

But there is no doubt that Jota's injury troubles pose a problem. His injury history suggests he will always miss matches — since signing for Liverpool in 2020, he has been sidelined for 93 in total — and Darwin Nunez is an inconsistent back-up option at best; he only has four goals so far this season.

Luis Diaz has done well enough through the middle in some matches but against Nottingham Forest, the trajectory of the game completely changed when Jota entered the field. The 28-year-old is scoring or assisting at a rate of once every 96 minutes so far this season but the issue is that he isn't on the field anywhere near often enough.

The ideal scenario would be that Liverpool could bring in another number nine to play the majority of the minutes — an upgrade on Nunez, who could guarantee 25 goals — with Jota used almost as a luxury player. That would then allow Diaz and Cody Gakpo to share the left wing berth and Mohamed Salah and Federico Chiesa to split the action on the right.

It was always clear that Jota's injury troubles could cause an issue but just as he makes a telling difference, he has suffered another ill-timed setback. While he might yet be available to play against Brentford (and if not, he isn't expected to be far away), this was the latest reminder that as important as he is when he is on the pitch, that simply doesn't happen often enough. In the summer, a number nine has to be a priority.