Jorge Molina's agent has confirmed Celtic tried to sign the Real Betis striker before the transfer window closed.
The Bhoys made an improved offer for the 29-year-old on Monday, but it was rejected by the Primera Liga club.
Agent Domingo Sevilliano has hinted his client was interested in a move to Parkhead, although it was out of their hands.
The clubs held talks prior to the transfer window closing, however, Betis wanted a higher figure to part company with Molina.
"In the past week, I have presented offers to Betis, but they didn't get back to me until the weekend," confirmed Sevilliano to the Daily Record.
"On Monday, Celtic increased the money and there were negotiations.
"Their offer was interesting to Jorge, but it wasn't up to the player. It was down to Betis wanting more money."