The 32-year-old has been sidelined with an Achilles injury for almost a year, after picking up the problem in October 2016, but Wenger has stated that he will start running again on Thursday.
Reports have claimed that the Spaniard may be forced to retire due to the injury, but Wenger believes he will be back in action in 2018.
“You speak about Santi, he is having his first run today. So that is quite positive,” said Wenger, as quoted by talkSPORT.
“The flexibility of his ankle looks good, his mobility is good and now it’s back to getting back to full fitness without having any set-backs. So it’s very difficult to predict when he will be available again.
“But overall, I think it’s very difficult to set a time. Not before Christmas, that’s why I didn’t involve him in the Europa League, but overall I hope that after Christmas he will be available.
“But he has not played for over a year now. He’s had a few surgeries so you are always cautious to set a time or date, but overall, yes it looks positive.”