Andrei Arshavin has told Sport Express he had to leave Arsenal after his time there left him on the brink of depression.
Arshavin, 32, secured a return to Zenit Saint Petersburg earlier this week after a mixed four years in North London.
Joining the club for a reported £15 million in 2009, he played just 80 minutes of Premier League football in a disappointing final season with the Gunners.
Departing Emirates Stadium on a free transfer when his contract expires on July 1, Arshavin admitted to Sport Express that his reduced playing time had a significant impact on his mentality.
"The fact is I didn’t want to stay in England, this was clear since January,” Arshavin said, “I don’t regret anything, but I had to leave. It was a punishment sat on the bench.
"To train even though you know you won’t play - it is psychologically difficult. I nearly suffered depression, but I didn’t because I’m mentally strong. The monotony of life there was crushing me."
Arsenal manager Arsene Wenger had previously questioned the Russia international’s mentality after choosing to leave him out of the club’s 1-0 defeat to Sunderland in 2009.
Citing a disappointing World Cup qualifying campaign for Russia as the reason behind his lack of focus, Wenger said: “Andrei is very down. He came back from international duty very low and that’s the main reason I did not play him from the start against Sunderland.
"You want players to be 100% focused and play a game like it’s a matter of life or death, so it is impossible not to be down if you don’t win. If you care, you are down.”
Now back in his homeland after signing a two-year-deal with Zenit, Arshavin said he is eager to make a return for the national team.
Speaking to the club’s official website, the 2006 Russian Player of the Year said: "I am very happy to put on Zenit's shirt again.
"Of course I want to return to the national team as well. I do not know if the move to Zenit will help me, I just want to play football and play in my home city."