The Whites midfielder, one of Marcelo Bielsa's most reliable and consistent players this season, had a day to forget in Saturday's early kickoff at Queens Park Rangers.
Phillips gave the ball away an uncharacteristic number of times in the first half, and once again was poor on set pieces.
Although he threatened with a good effort just after the hour mark, a moment of madness ended up summing up his side's day.
With two minutes left in the game, the 24-year-old lost control of the ball midway inside the QPR half and, as it moved away from him towards Geoff Cameron, he recklessly lunged in on his opponent, a foul which earned him a straight red card.
As well as pretty much costing Leeds any hope of getting something from the game late on, Phillips is now likely to be punished with a three-match ban, and with the teams in the playoff places snapping at the Whites' heels, it could prove very costly.
Here is how some Leeds fans on social media reacted to Phillips' display and dismissal:
Are we going to pack it in with Phillips on set pieces yet? We haven’t looked threatening from a corner in months #lufc— TomAxe (@tom_axe) 18 January 2020
Phillips is the most overrated player to ever wear a Leeds shirt. There, I said it. Bring on the bashing #lufc— Andy (@Bomlombardlufc) 18 January 2020
There’s a lot about LUFC that is becoming routine including stupid tackles by Phillips!— Paul Howard (@paulshoward1950) 18 January 2020
fully deserved red small squad no decent strikers no money to buy top players 18 months of not signing a top striker if we don't go up bielsa orta and the chairman must take the blame— ian burns (@ianpburns1) 18 January 2020
And Phillips just showed what an immature player he really is, that's in his game and with our small squad we can Ill afford to lose players through utter stupidity. Another embarrassing day #lufc— Craig Smith (@craggsy82) 18 January 2020
Sell Phillips now. Knows what he’s doing there, head went. Get the money and invest #lufc— Ryan Day (@RyanJDay) 18 January 2020
Not good enough today. Quite frankly, Bamford isn’t good enough. But would another striker find the positions to score them? I don’t think so. If Phillips doesn’t have the temperament, then sell him now. Can’t be having a walking red card.— ⚪️ LUFC Chat ⚪️ (@LufcChat) 18 January 2020
The #lufc crumble is well & truly on. No composure in front of goal, no composure in key moments. Phillips has potentially cost us promotion there. Couldn't care less if he's "Leeds". Pathetic.— Ryan Owen (@whiterosephilly) 18 January 2020
Ridiculous challenge from Phillips. Absolutely deserved that red card. Sums up our day entirely that. #LUFC— Mark Bateman (@MGB8man) 18 January 2020
Losing Phillips for next three games is worse than losing three points today. #lufc— Paboy (@paboy113) 18 January 2020
Leeds fell behind in controversial circumstances on 20 minutes when Eberechi Eze's free kick struck both of Nahki Wells' arms before he tapped into the net from six yards.
Marcelo Bielsa's charges dominated possession in the second half but were unable to force an equaliser, Patrick Bamford failing to score from the spot as his penalty was saved, and Pablo Hernandez hitting the post with a free kick.
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