The Ashes: Mitchell Johnson shocked by Jonathan Trott's mental woes

England's main tormentor in the first Ashes Test Mitchell Johnson said on Wednesday that he was shocked to hear of Jonathan Trott's stress-related illness, sympathising after dealing with his own mental demons.

Batsman Trott withdrew from the Ashes tour of Australia on Monday to deal with what was widely reported to be depression.

Johnson knows all too well about the pressures of international cricket, suffering his own dark days when he hit a form slump while playing in Sri Lanka and South Africa in 2011.

He later revealed he was mentally exhausted, and only a toe injury that forced him out of the game for six months saved him from contemplating retirement. "I really just wanted to get way from the game and step back," he said at the time.

The time away rejuvenated Johnson and he bounced back, twice capturing Trott's wicket in fiery spells during the first Test in Brisbane, prompting Australian opener David Warner to call Trott "weak".

"It was a real shock for me," Johnson told reporters of the English veteran's departure.

"It can be tough at times when it's not going so well. You start to think about every little thing that's going on in your life when you should be focusing on one thing.

"It seems maybe he's thinking that way at the moment, and just needs to just get away from the game.

"For me, when I had my toe injury, it was great to get away to freshen up mentally.

"I just wish Trott the best. Hopefully he can come back later in the tour or in the future, because he's a great player for England and he's done exceptionally well."

Trott, batting at three, has been a stalwart of the England team, accumulating 3,763 runs at an average of 46.45 in his 49 Tests.

Joe Root is seen as a possible replacement for the second Test in Adelaide next week, moving up the order from six, with all-rounder Ben Stokes potentially coming into the side.