Steven Fletcher is in contention to play in Wednesday's final pre-season outing against La Liga side Villlarreal this weekend.
The 31-year-old has featured in two behind-closed-door friendlies this week. He played 30 minutes of Saturday's win over NAC Breda and the first half of the midweek defeat to Bradford City as he steps up his recovery from a knee injury.
Manager Jos Luhukay told The Star: "Steven has made good progression. He played 45 minutes in the Under-23s match.
"He felt well after the game but we must assess him in the next couple of days.
"We must have a little bit of patience with him but he is working hard on his comeback."
Fletcher, whose last competitive match came against Hull City on December 2, will be hoping to get some minutes under his belt this weekend to prove his fitness ahead of the 2018/19 Championship season.
"We must think about what is best for him," said Luhukay. "As well as training, it is important you feel the rhythm from the game.
"Of course, we are happy Steven is going in a positive way."
With just over a week to go until the big kick off, Luhukay is unlikely to take any risks with players carrying knocks when they welcome Villarreal to Hillsborough.
One thing is for sure; Luhukay will be expecting to see a big improvement on the disjointed performance they produced in Tuesday's loss to Mansfield Town which had few, if any, redeeming features. After a positive opening, Luhukay claimed it was "too easy" for Mansfield to press them in possession.
He said: "We have to find solutions and possibilities to create and score more chances. Mansfield defended very strongly and didn't give a lot of chances away but we must work on our offensive transition."