Andy Little will undergo a scan today after lasting just 41 minutes on his Blackpool debut.
The Preston loan striker looked lively at Southend before falling to the ground clutching his hamstring.
Pool hope the injury is nothing more than a strain as a tear could see him miss a huge chunk of his Bloomfield Road spell, which runs out on January 2.
Manager Neil McDonald said: “We’ll have to see if it’s just stiff or he’s tweaked it. That was really disappointing as I thought he did well. His link-up with Mark Cullen was good and they created chances.”
The 26-year-old arrived from Deepdale last Tuesday, having been left out in the cold by manager Simon Grayson.
His lack of any competitive games since April made his selection a gamble but McDonald said: “He’d had a couple of good days training and looked really sharp. I wanted to put him up there and get going.”
The early signs were good as Little’s header rattled the underside of the bar on 26 minutes. McDonald said: “It’s difficult to adapt to new training and a new squad but I thought he did well. I brought him here to score goals and he’s had a really good chance.
“I was a bit critical of him in the changing room before I saw the video, but his header was good and should have gone in.”
Little has been ruled out of tomorrow’s trip to Port Vale.