While not naming Manchester United, it's understood Martinez was referring to the Premier League champs when discussing Baines this morning.
He told the Liverpool Echo: "Before we went to Austria one club officially contacted ourselves with an offer, and it was a final offer.
"They put something over and the valuation wasn't anywhere near the quality of Leighton Baines.
"That was the end of it but since then there's been all the speculation, which has been part of what the transfer window is.
"There's never been another club or anyone else putting in an offer for Leighton. Since then we've moved on and we're continuing to focus on the start of the season."
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