Millwall boss Neil Harris rued a late penalty decision that went against his side as they slipped to a narrow 1-0 defeat at Stoke.

Saido Berahino's header just after the hour ensured that Stoke moved to within touching distance of the Championship play-off positions on a gloomy winter afternoon in Staffordshire.

In a contest that lacked real quality throughout, Millwall almost led within the opening two minutes when Jack Butland was forced into making a low stop to his left when Ryan Shawcross sliced Jed Wallace's cross from the right towards his own goal.

Harris was frustrated with the penalty decision that went against his struggling side when Lee Gregory was brought down in the penalty area by Bruno Martins Indi, but referee Chris Kavanagh turned down the appeals.

He said: "I've watched it (the incident) from two different angles and Lee not once takes his eye off the ball, he looks to take the ball down and the defender goes into the back of him, anywhere else on the pitch, in our penalty area, the referee jumps to give it.

"I thought Stoke were better with the ball than us, they are a possession-based team, but in the second half, one contact in our penalty and it ends up in the back of the net.

"We should have scored early and Coops (Jake Cooper) should have scored, we should have had a penalty and on the balance of play, the chances we created, we should have got something from the game.

"I thought it was a really, really strong performance from us, winning games is the business we are in, and today was an excellent away performance for us."

Following half-time, Stoke upped the tempo in front of an expectant home crowd, and led on 61 minutes when Berahino reacted first to plant his header from Tom Ince's right-sided cross beyond visiting goalkeeper Jordan Archer.

The South-East Londoners should have salvaged a point late on when Cooper glanced Shane Ferguson's corner over the crossbar, before the controversial penalty decision.

Stoke boss Gary Rowett feels his side can perform better, despite them recording a third straight home victory.

Rowett said: "It is a win, it is a clean sheet, we know we can perform better, I've been saying that for a lot of the home games but I am getting to the point if I'm saying this every post-match interview that we've won and I'm disappointed, I'll happily be really disappointed until the end of the season.

"That is three home games that we have won in a row, it is another clean sheet, yes we can play better, yes we can see the game out with a little bit more control and a little bit more composure, but Millwall are the type of team that test you, they are very direct and they make it difficult.

"We still think that we are five or 10 per cent off where we need to be, but we are winning games and we are on a good run."