Liam Trotter and Dany N'Guessan are out of the game.
Midfielder Trotter and on-loan Leicester striker N'Guessan are sidelined with hamstring injuries, but both are on course to be fit after the international break.
Winger Chris Hackett came off during the midweek Carling Cup win over Morecambe with a back spasm and is doubtful.
Midfielder Therry Racon is still sidelined with ankle ligament damage and striker Shaun Batt's recovery from a cruciate injury was disrupted by a calf strain, but both hope to be back within a month.
Skipper and centre-half Paul Robinson, who is a transfer target for Reading, and striker Darius Henderson return after they were rested against the League Two Shrimps.
Barnsley are expected to include new signings Danny Drinkwater and Cameron Park in their squad.
Manchester United midfielder Drinkwater, 21, and Middlesbrough winger Park, 19, signed on loan for six and three months respectively this week and give manager Keith Hill a welcome selection dilemma.
Hill said: "I'm not going to give too much away. The players who are recovering from injuries probably aren't ready to play.
"We got a great performance last week out of Andy Gray, but he was only in the squad as a necessity."
Gray has been struggling with a hip problem in recent weeks, while fellow strikers Ricardo Vaz Te (thigh muscle tear) and Reuben Noble-Lazarus (ankle) are not expected back from injury.
Defender Miles Addison and midfielder Nathan Doyle (both groin) also remain sidelined after sitting out last week's first win of the season at Reading.