Barnsley completed their season with a 3-0 loss at champions Newcastle United so finished in 14th position.
The hosts dominated the game but the Reds defended well and goalkeeper Adam Davies made a string of excellent saves to keep the score down.
Barnsley, after a run of two wins in their last 18 matches, finished seven points above the relegation zone and 22 off the play-offs.
Paul Heckingbottom made two changes to the side that draw their final home game of the season against Burton Albion eight days earlier. Marley Watkins and Gethin Jones dropped to the bench with Ryan Hedges and Saidy Janko returning to the starting 11. After a dull first quarter of the game, which featured only a 20-yard Ryan Kent shot which was easily held by the home goalkeeper, the home team took the lead.
Christian Atsu backheeled the ball inside the Reds box to overlapping right-back DeAndre Yedlin whose low cross was flicked home by Ayoze Perez.
The Magpies were having great joy down Barnsley's left against the overwhelmed Callum Elder who received little support from winger Ryan Kent. Atsu had a 20-yard shot tipped over by Adam Davies after more good work from Yedlin then the goalkeeper denied the same player with an even better low save to his right.
Barnsley's left side was again exposed when Perez made a bulldozing run down the byline from the right wing and pulled the ball back but it was blazed badly over by substitute Massadio Haidara who had earlier replaced the injured Isaac Hayden. Barnsley went into the interval having been dominated for the second half of the first half.
Perez almost doubled his lead 20 seconds after the break but fired straight at Davies having been played through on the left of the area. Davies again made a one-on-one save, this time from Jack Colback who was at a tight angle on the right side of the six-yard box after some intricate play in the Barnsley box.
The second goal eventually came just before the hour when Davies made yet another top stop, spring to his right to deny Perez, but centre-back Chancel Mbemba fired in the rebound. Davies produced his latest excellent save to tip over Aleksandar Mitrovic's header from a corner by Jonjo Shelvey, who then hit the left post with a low shot from the edge of the penalty area following a superb run.
Barnsley almost halved the deficit with six minutes left when substitute Watkins had the goal at his mercy when meeting a right-wing cross by headed straight at goalkeeper Rob Elliot, who then saved with his legs from a long range shot by another replacement Elliot Lee.
But it was a home substitute who made it 3-0 as Dwight Gayle went clean through and beat Davies with a cool finish.
