Steve Harmison believes England will face a tough time trying to replace Andrew Flintoff.
Flintoff, 31, is to retire from Test cricket at the end of the summer after realising his body can longer cope with the demands of the five-day game.
And Harmison accepts the Lancashire all-rounder will leave a huge void in England's Test team.
"It's disappointing from an Englishman's point of view," Harmison told Sky Sports.
"It will be interesting to see how England go in future years after Andrew's gone. When Ian Botham retired it probably took 20 years to get another cricketer who could do somewhere near what Beefy could do.
"There's space for an all-rounder out there to come and fill Andrew's shoes because he is a big miss, no matter what anybody says.
"Someone to bowl at 92, 93, 94 miles per hour, bat in the top six which he has done for England in the past and stand at first slip... it's a massive, massive hole to fill.
"He'll be a massive miss for Test cricket because any team without Andrew Flintoff in, any England side, will be a weakened side."
Harmison acknowledged, though, that the injury-plagued Flintoff had little option with his long-term well-being at stake.
He added: "From somebody who is close to him - I think the world of him - to see him go through what he goes through, he comes back and the criticism he gets for it... I sometimes think 'why don't you just stop playing Test cricket because it seems to be that that's getting you injured?'
"He can't keep pounding his body, getting injured and coming back."
Flintoff will remain part of the England scene for one-day and Twenty20 internationals, and Harmison feels he should not be criticised for concentrating on the shorter forms of the game.
"We all know the cricket schedules are... not horrendous but there'll be a lot of cynics out there - a few sit in the commentary box and say 'what about the IPL, you go off chasing money and this, that and the other'," continued the Durham paceman.
"But they do play a lot of cricket. I see both sides of the fence. I do personally think we play a hell of a lot of cricket in a short period of time with not much rest.
"It's up to individuals but in Andrew's case his body started to let him down a bit.
"He's looking at his health and sanity in the future, (ensuring) that he's not a crippled old man when he's 40 years old, having played two or three years more of Test cricket."