Barnsley lead Hull City 1-0 to frustrate the visitors in their bid for automatic promotion.
Hull's hopes of cruising to automatic promotion were dashed in the fourth minute when Jacob Mellis drilled in the opening goal off the underside of the crossbar.
The visitors went close to pulling a goal back just moments after the restart but George Boyd's lob was cleared off the line by Tom Kennedy.
Barnsley settled down following Hull's reaction to the goal and the hosts looked dangerous as they continued to probe the visiting defence.
A Hull fightback didn't come before the break and Steve Bruce's side are left with a mountain to climb if they are to secure promotion on Saturday.