The Republic of Ireland international missed last weekend's 1-1 draw with Sunderland after scoring two goals in three outings prior and Koeman is thrilled to have him back for the crunch clash with the Potters.
"Shane Long is coming back to the team," Koeman said.
"Shane is having a great period in the team, he's very dangerous, he's a fast striker, he has really the total confidence what you need as a striker at the moment and he is an important player for us at the moment."
Long has netted seven goals in 20 league appearances this season to lead the way for the Saints.
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