Cardiff moved back into the Championship automatic promotion places with a 1-0 victory over Middlesbrough.
Bluebirds skipper Sean Morrison headed the winner after 34 minutes to seal all three points at the Cardiff City Stadium.
The hosts’ fourth win in six matches was enough to move above Derby, not in action this weekend, and Aston Villa, who were beaten by Fulham.
Middlesborough fell to 10th in the table and are now four points adrift of the play-off places.
Middlesbrough manager Tony Pulis believes Morrison fouled Gibson in the act of scoring Cardiff’s crucial winner.
He said: “In the first half we found it difficult to cope with Cardiff. They are very good at what they do, they have an identity and they play to that identity.
“Set plays were always going to be important. Looking back at it Morrison was all over Gibson but we didn’t get that decision and that was the decisive moment.
“Cardiff have five or six players over 6ft 3ins let alone 6ft, so it was always going to difficult, but I have no complaints.
“We have 14 games to go and we have to put a run together. The pitch was difficult for the players today.
“We had good footballers in the team with Stewart Downing, Grant Leadbitter and Jonny Howson but Cardiff squeezed the life out of us.
“They are second in the league for a reason, they have an identity and they play to it whether you agree with it or not.”
Chances were hard to come by for both teams in the opening 20 minutes as Cardiff looked to break down a Boro side who had won three of their last four away matches.
Junior Hoilett had a chance to add to his tally of 11 goals when he linked up with Callum Paterson, but he could only fire his effort high and wide.
But Cardiff’s muscle overpowered Tony Pulis’ stubborn side after 34 minutes.
Hoilett swung a dangerous delivery towards the far post after Kenneth Zohore was hauled down on the edge of the area.
Morrison towered over Ben Gibson to guide the ball past Darren Randolph for a 1-0 lead.
Joe Ralls had the chance to make it 2-0 when he battled his way past Grant Leadbitter to fashion a shooting chance, but his left-footed shot flashed wide.
Middlesborough almost levelled after 54 minutes when Leadbitter sparked a swift counter-attack with an inch perfect pass to Stuart Downing.
The former England winger charged towards Neil Etheridge’s goal, but failed to crown his 300th start for Boro with a goal as he dragged his effort wide.
The hosts then had a chance to guarantee three points when Morrison flicked the ball on from a Paterson long-throw.
Hoilett looked certain to add a goal to his earlier assist, but Randolph spread himself to deny the Canadian from point blank range.
Substitute Loic Damour volleyed an effort straight into the clutches of Randolph in the final 10 minutes and the hosts held out to record their 15th clean sheet of the season.