Brentford striker Scott Hogan has suffered a setback in his rehabilitation from a serious knee injury.
Scott has been outside for more than two months as he worked his way back from reconstructive surgery.
The 23-year-old suffered the injury at the end of August, in a match against Rotherham United.
After spending time with world renowned Conditioning Coach Bill Knowles in Philadelphia in January, Scott had been taking part in drills with the squad over the past few weeks.
But he picked up another injury during training on Tuesday, April 21.
Neil Greig, Brentford FC Head of Medical, explained: “It's with great disappointment that I have to report that Scott has this week suffered an unfortunate setback in his recovery from significant knee surgery.
“Whilst participating in an unopposed team passing drill at Jersey Road on Tuesday, Scott caught his foot in the turf whilst making a side-foot pass and has sustained a further injury to the same knee of a significant nature.
“The injury has been scanned and the orthopaedic consultant managing Scott's case has assessed the knee with the disappointing outcome that Scott will now have to undergo a further surgical procedure to repair the injury.
“At this stage the timescales for recovery are difficult to predict and I would anticipate knowing more on that front following surgery, which is likely to take place next week.
“Scott's progression during his rehabilitation and his achievements to date have been remarkable, with every objective that was set being surpassed.
“Scott had been joining into low level team training for the past three to four weeks, as per his plan, and was beginning to build his confidence in the environment.
“Indeed, Bill Knowles visited the club from the USA last week and reported that Scott was in excellent shape and his aim of being fit for pre-season training was well within sight.
“Of course, nobody is more disappointed than Scott himself and his dedication to recovery has been first class.
“Myself and my staff share this disappointment and will now reassess our aims and refocus on setting new goals for Scott's immediate and long-term care.”
Mark Warburton, Brentford FC Manager, added: “This is a devastating blow for a young guy that has worked so hard over the last eight months, along with the medical team, to get back to full fitness.
“Scott has been taking part in technical practices and passing drills and it has been a delight to have him back.
“He is hungry to play football.
“It happened during an innocuous passing drill on Tuesday and there was no-one near him.
“It is a blow for him and for us.
“After all the work he has done it is a blow but we have no doubt about his character.
“The staff and players will get him up and I have no doubt about Scott’s desire to be the best he can be and a great player for the Club.
“Scott is a top lad and a top talent and I have no doubts that he will enjoy a first class career.
“I look forward very much to watching his return to First Team action when his rehabilitation is complete."