The 23-year-old, a key figure in the Minstermen’s promotion and FA Trophy double of 2011-12, joined the club from the Lancashire coast during the summer.
Since then, Blair has made 10 appearances for Fleetwood and scored three goals. He started Tuesday night’s defeat to Scunthorpe and is likely to be the centre of attention when the two clubs meet today in York.
However, Worthington said: “We can’t afford to focus on one individual.
“Football is a team game and we need to deal with Fleetwood’s team, not just one player.
“Matty was a big player for this club, especially in terms of bringing us back into the Football League. He was offered a contract several times last season, but exercised his right to let the existing contract run out.
“That was perfectly within his rights and he decided to move on. We will welcome him back, but the focus has to be on a very good team in Fleetwood and not just one player.”
York will go into today’s game buoyed by the midweek performance that brought a point from the trip to high-flying Chesterfield.
Worthington’s side led 2-0 after an hour, but the Spireites hit back to claim a 2-2 draw. The York chief is adamant that the point won was a good one.
He added: “We came up against a very, very good team and I was delighted with the attitude and performance we put in. Of course, at 2-0 up you want to win the game.
“But Chesterfield are a good team with some very good players. They threw everything bar the kitchen sink at us in the second half and I took a lot of positives from how we played.”
Back-to-back home games against Fleetwood and then Scunthorpe United on Tuesday offer an opportunity for York to move up the table.
Worthington added: “We are positive at home and the players really believe in themselves.”