Middlesbrough lost for the second home game in a row after letting a lead slip as they were beaten 2-1 by Preston.
Boro were left fuming at referee Keith Stroud's controversial decision to send off defender Daniel Ayala just after the hour when they led 1-0 courtesy of Ashley Fletcher's 32nd-minute opener.
In-form Preston, who are now unbeaten in 11 games, levelled from the resulting free-kick when Paul Gallagher's brilliant effort found the net.
With eight minutes remaining substitute Jayden Stockley headed in the winner to lift Preston to within two points of the play-off zone which Middlesbrough are now in danger of dropping out of.
Middlesbrough manager Tony Pulis recalled defenders George Friend and Aden Flint after injury, while Preston brought back Ben Pearson to the midfield after suspension.
It was full-back Friend's introduction at the expense of top scorer Britt Assombalonga against Brentford on Saturday when Middlesbrough led 1-0, that sparked fury and was followed by a 2-1 defeat.
They got a positive start. Jonny Howson went close first when his long-distance drive forced a fine save from goalkeeper Declan Rudd.
Ayala also shaved the upright when he stretched to meet Fletcher's flick on from Lewis Wing's corner.
A few minutes later when John Obi Mikel turned and drilled low against the inside of the near post and Preston cleared their lines.
Middlesbrough got the break they deserved just after the half hour when Fletcher's effort deflected off Jordan Storey after Mo Besic's run and pass had played the striker in.
There were further chances for Middlesbrough to increase their advantage before the break.
Rudd made a strong save with his legs to deny Howson, while Preston's number one also raced off his line to deny Assombalonga after Fletcher's flick on had played him in behind the visitors' defence.
Middlesbrough continued to miss chances after the restart. Howson somehow missed the target from 12 yards when it looked easier to convert Wing's cross.
Stroud sent off Ayala just after the hour when the Middlesbrough player went to ground with force on Brandon Barker and the official deemed it was reckless.
That presented Gallagher with a chance to level and he succeeded, curling the ball around the wall and inside the far post.
With eight minutes remaining Preston celebrated the winner when Stockley headed in from close range as Pearson's deflected shot dropped invitingly for him.
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