Downing - in his second full season at Upton Park - is preparing to represent England for the first time since 2012 following his brilliant run of form for West Ham.
But an England recall seemed like a distant dream for Downing at Liverpool, where he endured a torrid two-year spell that came to a head after he was told to play as a full-back by manager Brendan Rodgers.
While the 30-year-old was content to make the switch to defence in order to put together some much-needed game time, he revealed it was the lowest point of his career.
"I was out of the team [at Liverpool] so for me just to play and get back in the team was a big thing," Downing said.
"At left-back it was obviously difficult, but it was a chance to get back into the team for me, so I had to go along with it.
"I wasn't happy playing left-back. It is not my natural position. But I knew from then it was the time for me to move.
"I was getting signals other players were coming in, and I was getting used at left-back when I was a winger. I think you know when the writing is on the wall for you under a manager or at a club.
"The West Ham move came at a good time for me and was a chance to go out and play football regularly and play under a manager who wanted me to play every week."
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