Louis van Gaal felt the pressure on his shoulder build further as Manchester United suffered a 2-1 home loss to Norwich City – their fourth Premier League game in a row without a win.
Wayne Rooney, making his 500th appearance for the club, returned from injury and helped United make a promising start at Old Trafford, but they were stunned by Cameron Jerome's goal shortly before the break, as Norwich capitalised on their first chance of the half.
Alex Neil's side shocked the hosts again early in the second half as Alex Tettey prodded in a second, with United failing to make their control of possession count against a disciplined visiting defence.
Anthony Martial, fresh from claiming the Golden Boy prize for 2015, gave United a lifeline with a calm finish from close range in the 67th minute as United poured forward in the torrential Manchester rain.
Juan Mata came close with a free-kick, but Norwich held on for only their second win in 20 away games in the top flight, adding to the scrutiny on Van Gaal as talk of a move for Jose Mourinho looks set to intensify.
United – beaten by another promoted side last time out in the shape of AFC Bournemouth – started on the front foot looking to inject the attacking verve Old Trafford has so often called for this season, with Memphis Depay curling one effort narrowly over before Rooney dragged a shot wide after a good Mata run.
Depay just failed to connect properly with a Rooney cross as the home side continued to dominate, but Norwich kept them largely at arm's length and began to grow into the game as the half wore on.
And the visitors snatched the lead just seven minutes before the interval. After Tettey's good break, Nathan Redmond turned inside Ashley Young before teeing up Jerome, who side-footed past David de Gea from close range despite the goalkeeper getting a hand to the ball.
The Stretford End gave a rousing cheer in an effort to encourage United, but Norwich sent the away fans into raptures after another clinical counter-attack 10 minutes after the break.
Jerome burst clear of Phil Jones after Rooney and Michael Carrick had lost possession near halfway and Tettey latched onto his pass before toe-poking the ball past De Gea and into the bottom corner.
United had peppered the Norwich penalty area with unsuccessful crosses, but one finally proved telling midway through the second half, as Martial pounced on Rooney's flicked header from a Mata delivery before firing high past Declan Rudd from 12 yards out.
Mata's free-kick brought a good save out of Rudd, while Chris Smalling – playing as a makeshift striker in injury time – headed the ball wide after running clear through on goal, but Norwich held on for a vital three points in their bid for survival, while extending United's winless run in all competitions to six matches.
