Daryl Janmaat saw red as Newcastle United crashed to a 2-0 away defeat at Swansea City.
The Dutch full-back was given his marching orders four minutes before the break after picking up a stupid second-yellow for a pull on Jefferson Montero’s shirt.
It meant Newcastle - who were already 1-0 down to a Bafe Gomis goal- having to play a large chunk of the game with only 10-men.
Andre Ayew powered home a header seven minutes into the second half to condemn Newcastle to their first defeat of the season - and their seventh consecutive away defeat in the Premier League.
The Swans took the lead after nine minutes at the Libery Stadium.
Jonjo Shelvey’s defence-splitting pass played in Bafe GOMIS, who took a touch before rounding Krul to put the hosts 1-0 up.
Newcastle were on the ropes.
Janmaat was then booked after going through the back of Jefferson Montero, the Ecuador winger looking lively in the opening stages.
Montero was the star of the show, with Newcastle unable to deal with his pace or trickery.
Gabriel Obertan had two efforts on goal but they were both relatively comfortable for Lukasz Fabianski as Newcastle failed to build any pressure.
Papiss Cisse’s was crowded out at the near post after the most promising move of the match, with Swans defender Federico Fernandez injured for his troubles.
Then, four minutes from the break, Janmaat picked up his second yellow card of the half after pulling back Montero 70-yards from goal and in full view of referee Mike Jones.
A reckless mistake and one which cost his team, down to 10 men for the rest of the game.
Montero hit the post just before the break as Swansea went in leading 1-0.
Half-Time: Swansea 1 Newcastle 0
McClaren made a switch at the break, with Steven Taylor on for Sissoko - who had limped off - as Newcastle reverted to a 4-4-1 formation, with Chancel Mbemba at right-back.
Swansea weren’t holding back though and looked to press home their advantage within minutes of the re-start.
Sigurdsson curled a brilliant effort from 20-yards but it crashed off the crossbar and didn’t cross the line.
Soon it was 2-0. Montero with the cross from the left-hand side found Andre AYEW, who jumped higher than Coloccini to powerfully head high past Krul.
Newcastle were all over the place and McClaren moved to replace Cisse with Rolando Aarons - leaving them without a striker on the pitch.
Wjinaldum was the furthest forward but Newcastle struggled to string any long periods of possession together.
Instead it was Ayew who almost made it 3-0 midway through the second half, just failing to properly connect to another Montero cross.
10-man Newcastle struggled to maintain possession and in truth, the game was over as a contest as soon as Ayew had made it 2-0.
Aleksandar Mitrovic came on as a late sub and was booked again with two minutes for an over the top challenge on Neil Taylor.
A lot to ponder for McClaren then ahead of a daunting trip to Old Trafford.
Full-Time: Swansea 2 Newcastle 0
Swansea: (4-2-3-1) Fabianski, Naughton, Fernandez, Williams (C), Taylor, Cork, Shelvey, Sigurdsson (Britton, 86), Ayew (Dyer, 72), Montero (Routledge, 76), Gomis.
Subs Not Used: Nordfeldt, Rangel, Bartley, Eder.
Booked: Ayew (49), Naughton (61)
Goals: Gomis (9), Ayew (52)
Newcastle (4-2-3-1): Krul, Janmaat, Coloccini, Mbemba, Haidara, Colback, Anita, Sissoko (Taylor, 45), Wijnaldum, Obertan (Mitrovic, 82), Cisse (Aarons, 54).
Subs Not Used: Darlow, Williamson, Perez, Tiote.
Booked: Janmaat (17), Mitrovic (84)
Sent off: Janmaat (41)
Referee: Mike Jones (Cheshire)