Gary Hamilton has urged local football fans to turn out in their numbers at Mourneview Park on Thursday night to support Mark Farren.
Fundraising efforts to help former Derry City and Glenavon striker Farren have already exceeded £31,000.
The 33-year-old recently underwent a third bout of surgery for a brain tumour and now requires specialist treatment in Germany – with a six-week course costing in the region of £25,000.
Donations have been pouring in for Farren, and on Thursday Glenavon will play a team of his former team-mates in a special fundraising match at Mourneview Park (7.45pm).
Players from the Derry City side that qualified for the first round of the UEFA Cup in 2006/07 before losing out to Paris St Germain will feature in Lurgan – including Eddie McCallion, Barry Molloy, Stephen O’Flynn, Kevin McHugh, Ciaran Martyn and Paddy McCourt.
“Mark is facing the fight of his life, and he deserves all the support we can give him,” Glenavon boss Hamilton said.
“He was a fantastic player during the time he was with us. We love our stats here at Glenavon, and when he came here he played 16 games and scored 10 goals. He also had something like 37 or 38 shots, and missed the target just twice.
“You will struggle to find a footballer with stats like that. He was a great player.
“We are lucky we can still enjoy football, but it has been taken away from Mark.
“It has been great seeing people unite in helping the fundraising initiative.
“I would urge everyone to come out on Thursday night and support Mark once again.
“Thursday is all about Mark, and it is great seeing a lot of the former Derry City lads lend their support to the game.
“Mark helped Glenavon progress in the direction we wanted. We wouldn’t be where we are today if Mark hadn’t played for the club.”
The football fraternity has joined in their support of Farren in recent days.
Everton and Republic of Ireland defender Seamus Coleman pledged £5,000 to the fundraising cause.
In a message, Coleman said: “Always tough to play against you in the Brandywell! Stay strong and best wishes.”
Farren’s former Derry City team-mate James McClean – another Republic international – was reported to have donated £1,000 to the fund.