Gordon Taylor is set to leave the PFA in June after 40 years in charge
Players' union chief Gordon Taylor denied his organisation had been "asleep" over dementia in football and wished he had "unlocked" the issue.
Former Blackburn striker Chris Sutton has accused the Professional Footballers' Association (PFA) chief of having "blood on his hands".
But Taylor told MPs in a parliamentary hearing into concussion in sport: "We've never been asleep on it.
"We were frustrated by the initial research, the data was not there."
Taylor, who is due to leave the PFA in June after 40 years in charge, said that when it found the correct data, which led to the landmark FIELD study published by Dr Willie Stewart in 2019, it "led to the best evidence in the world".
But he has been criticised by the likes of Sutton, who lost his football-playing father to dementia, and Dawn Astle, daughter of former West Brom striker Jeff, who was ruled to have died from a brain injury more commonly linked to boxing.
- Sutton: 'I believe heading a football killed my dad'
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They say that the union was too slow to act after Astle died, aged 59, in 2002.
Taylor, who said the PFA had spent over £1.5m on the issue "in the last few years" and £600,000 on research, said: "I think it is an unfair criticism because I know what we do and would be perfectly happy to show what we have done and what we intend to do, but it takes more than the PFA to be involved in this, it needs government as well."
"I wish we had managed to unlock [it]…we are doing our best along with every other issue in the game."
In written evidence, the PFA said it was aware of 276 former players with a neurodegenerative disease, 132 who were living, and 144 former players who had passed away.
It said it had spent £1.6m on support for 186 players and their families.
A strange parliamentary session, which also heard from rugby union players and jockey's association representatives, witnessed chair Julian Knight criticising former Newcastle and England striker Alan Shearer for refusing to attend one of three hearings on the issue.
Shearer has made a BBC documentary on dementia in football.
The hearing was also criticised by Sutton, a Blackburn team-mate of Shearer's, for veering onto other topical subjects rather than concentrating on concussion in sport.
At one point Taylor was asked about the failed European Super League and later on about Spotify owner Daniel Ek's interest in buying Arsenal.
Sutton tweeted: "DCMS now asking Gordon Taylor about the European Super League on a concussion and brain injury discussion after not asking questions they should have. What an absolute farce…"