Roberts had only been the pitch for 10 minutes after stepping off the bench when he was red-carded for what the referee saw in an off-the-ball incident with Jonas Olsson.

The striker, who had been sidelined with a stress fracture of the foot, looked bewildered at the decision, as did Allardyce.

Roberts will miss the first three games of next season, although Blackburn intend to appeal.

Allardyce said: "The referee said Jason had been sent off for punching Olsson.

"It is not a punch. It is not even an elbow in the face. He has swung around to get his arm away from Olsson, who is having a tug at him.

"I have had a look at it on the laptop and I cannot see how it is a straight red card.

"Jason is looking at missing three games unless common sense prevails and the appeals committee agree with my view on it."

Allardyce was angered that Roberts' sending-off overshadowed the 294th and final Blackburn appearance of playmaker Tugay, who is retiring after eight seasons at the club.

The Turkish star was given a standing ovation when he came off five minutes from the final whistle.

He told supporters at the end of the game: "I love you and will miss you."

Allardyce paid his own tribute to Tugay.

"He is not just a skilful player, he is much more than that. He is a really nice person," said the Blackburn boss.

"To be a Premier League player at 38 takes more than ability. You need the determination, the desire and the knowledge to go with it and he has all of those things.

"That is what makes him such a good player. He is also a tremendously fit guy. I wish him all the best."

Stand-in Rovers striker Chris Samba came close to breaking the deadlock only for his shot to hit the post.

Allardyce added: "I was pleased with a draw and a clean sheet in the circumstances."

West Brom manager Tony Mowbray felt his side, who are returning to the second tier, should have rounded off their campaign with a victory.

He said: "We probably deserved to win the game, given the chances we created. They hit the post but generally we defended well.

"Once again we have shown we can dominate games but we need to be more clinical. It is important we add that to our game.

"We had a lot of the ball and showed some good movement. Also we kept a clean sheet, which I hope is a good omen for next season."