Manchester United manager Louis van Gaal found no instant fix as a new era dawned in dispiriting fashion at Old Trafford where Swansea City's 2-1 victory on the opening day of the English Premier League reopened old wounds.
United's new captain Wayne Rooney had cancelled out Ki Sung-yueng's neat goal for the visitors shortly after halftime but Gylfi Sigurdsson's late strike condemned the Old Trafford side to their first opening-day top-flight home defeat for 42 years.
"It was a disastrous start for us but we have to move on," Rooney said. "We're not happy, the manager's not happy.
"We'll have to go through what went wrong during the week. We'll do that. I thought today we didn't play as well together as a team as we can do. We have to put that right."
Arsenal, tipped as serious title contenders this term, left it late to beat managerless Crystal Palace, with Aaron Ramsey pouncing in stoppage time to earn a 2-1 victory at the Emirates after the home side had slipped behind.
Tottenham Hotspur, who finished one place above United in sixth last season, began life under new manager Mauricio Pochettino with a 1-0 win at London rivals West Ham United thanks to a stoppage-time goal from new signing Eric Dier.
Promoted Leicester City twice battled back to draw 2-2 with Everton, while West Bromwich Albion and Sunderland also shared four goals - Saido Berahino scoring twice for the hosts.
Queens Park Rangers were beaten 1-0 at home by Hull City on their return to the top flight, missing a penalty in the process, while Aston Villa earned a notable three points with a 1-0 win at Stoke City - Andreas Weimann grabbing the goal.
Champions Manchester City visit Newcastle United tonight (NZ time) after Liverpool entertain Southampton while Chelsea will travel to promoted Burnley on Monday night (NZ time).
LACK OF PACE
A year ago almost to the day Manchester United enjoyed a comfortable victory at Swansea but it proved one of the few highlights for former manager David Moyes who was sacked in May.
After a buoyant pre-season campaign, the fans arrived on Saturday hoping new boss Van Gaal would right the wrongs of last season but the problems, notably a lack of pace and invention, returned to haunt the 20-times champions who looked vulnerable.
Van Gaal began with his favoured 3-5-2 system but changed to an orthodox 4-4-2 at halftime and this morning's evidence there will be lots of tinkering to come for the Dutchman who has won league titles with Ajax Amsterdam, Barcelona and Bayern Munich.
United dominated possession in the first half but offered little attacking verve against a Swansea side content to sit deep and wait for the occasional counter-attack.
One such break saw Nathan Dyer flick the ball on to Sigurdsson down the right and the Iceland international burst forward before teeing up Ki to beat keeper David De Gea just before the half-hour mark.
When Rooney hooked in Juan Mata's corner in the 53rd minute to restore parity and then clipped the post with a curling free kick the home side looked set for a comeback victory.
However, Swansea had other ideas and Ecuadorean substitute Jefferson Montero's dangerous cross caused problems in United's unfamiliar-looking defence and the ball eventually came to Sigurdsson, back at Swansea after leaving Spurs, to fire home.
"It's more than disappointing for the fans," said Van Gaal, who was without Netherlands striker Robin van Persie through injury and the likes of defensive stalwarts Rio Ferdinand and Nemanja Vidic, both of whom left in the close season.
"They are expecting a lot because we have won every game in pre-season. Then you lose the first match. That's disappointing for the fans, also for the players and also for me.
"It's a very bad day for us," he added.
Arsenal, with former Barcelona hitman Alexis Sanchez making his Premier League debut, were stunned by a Palace side reeling from the departure of manager Tony Pulis 48 hours earlier.
Brede Hangeland's glancing header gave Palace a 35th minute lead but Laurent Koscielny nodded home a free kick from Sanchez on the stroke of halftime to equalise.
Palace seemed to have earned a point with a stubborn defensive display but Welshman Ramsey tucked in a rebound after Mathieu Debuchy's shot was half-saved by Julian Speroni.
Palace had been reduced to 10 men shortly before Arsenal's late winner when Jason Puncheon received a second yellow card.
Ramsey's goal secured the day's only Premier League home win with Arsenal's relieved manager Arsene Wenger fully aware of the difficulties of winning the opening league fixture.
"If you look at the (earlier) results today, no home team won, we were the only one so it shows in the first game it is not easy to win. Our desire got us through," he said.
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