Arsene Wenger has revealed Danny Welbeck found life tough during his long injury absence but hopes he comes back a stronger player for Arsenal.
The England striker, who has endured two injury-ravaged seasons, made his first appearance of the current campaign as an 83rd-minute substitute in Saturday's FA Cup third-round win at Preston.
Welbeck suffered knee cartilage damage last May, just three months after he had returned from another long-term knee injury.
The 26-year-old former Manchester United forward consequently missed Euro 2016 and Wenger admits it was a difficult time.
Wenger said: "I think he went through certainly desperation because the setback he had was absolutely atrocious.
"The patience you need when you're that age - and to miss the European Championship on top of that, after missing the start of the season - it was terrible.
"But he worked hard and certainly it will make him stronger, what happened to him.
"He had to go through it and that was a very difficult moment for him. I think he suffered a lot but I hope - touch wood - that he now will have a clean career."
Wenger also revealed he allowed Welbeck to spend some time away from the club during his rehabilitation.
He said: "A football club is built for people who are competitive, so to some mentally it's difficult.
"We let him go outside as well and mixed his time. At the end of the day, when something like that happens to you, you have to deal with it on your own, but of course we spoke with him a lot and tried to support him."
Having overcome his troubles, Welbeck almost made an immediate impression on his return to action as he forced a fine injury-time save from Preston goalkeeper Chris Maxwell.
It would have given Arsenal a flattering 3-1 victory after Olivier Giroud had put them ahead just moments earlier, but it was a promising moment for the player.
Wenger said: "He has been out for such a long time, that just for him to get 15 minutes was great. I think I had a hesitation but in the end he nearly scored, so that's good."