Nigel Pearson says Andi Weimann will be ruled out for around two weeks but is awaiting feedback on the extent of Tommy Conway's hamstring injury suggesting he is likely to be sidelined for longer.
Conway, 20, limped off in the first half of Sunday's FA Cup draw with Swansea and was replaced by Nahki Wells. Weimann was also taken off in the final minutes of added time as City saw out the game with 10 men.
Nigel Pearson couldn't provide further details after the game but did reveal to BBC Radio Bristol that 'Andi's is probably not as bad as Tommy's'. Following scans at the High Performance Centre, the manager has confirmed he will be without both for the weekend visit of Birmingham but remained positive that the Austrian's issue was not as bad as first feared.
Speaking to Robins TV, he said: "We picked up a couple of injuries at the weekend which is disappointing because we have done exceptionally well to keep the squad more or less available outside of the more long-termers.
“We are not quite sure how long Tommy will be – we are still waiting for some feedback from the consultant and surgeon as to how they see that one. Andi will be around two weeks so that’s not too bad."
Weimann will also miss the FA Cup third round replay with Swansea next Tuesday and the home league fixture against Blackburn Rovers on January 21. He is likely to target the away trip to Huddersfield a week later for a return to action.
The injuries will leave Pearson light in attacking options. Antoine Semenyo and Nahki Wells are likely to start against John Eustace's side while youngster Sam Bell is also pushing for some first-team minutes. Chris Martin is also fit but has been left out of the last four matchday squads.
It could mean Alex Scott may play in the No10 role behind the strikers or, as Pearson mentioned, he may change the formation after a strong second half performance against Swansea when they went to a back four. He added: "We have options if we decide to change formation as well.
"Mark Sykes I think is very good playing as a wide player. You have to remember Kal Naismith started as a winger. We have options and it's always better to have more depth in terms of availability and different types of options but we'll be fine."
The injuries could impact the decision on whether to sell Semenyo this month. While there have been no offers for the Ghanaian, there is interest from Bournemouth and Burnley.
With a contract until 2024, City will have to sell the 23-year-old either this month or in the summer although they would be unlikely to cash in over the next three weeks unless they have a replacement lined up.
There was better news in regard to Tomas Kalas and his recovery. The defender, who hasn't started a league game since March 5, made a brief comeback from knee surgery with two substitute appearances in October before picking up further groin and knee issues.
Although he failed to feature in the Under-21s defeat to Cardiff on Tuesday, Pearson said last week how he will look to play him in a youth game to build up his minutes before bringing him back into the first-team fold.
“Tomas is back with his team-mates which is a very positive step for him," Pearson added. "Over the last three or four days he has been outside with a smaller group and outside on the grass for a week or so doing conditioning.
"It’s now about assessing his progression from here. I am pleased for Tom for him to get back out because it’s been a frustrating time but he has remained positive.”
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