MANCHESTER, England (AP) — Manchester United's post-Alex Ferguson dip has opened the door for a number of challengers in the Premier League this season, with Arsenal and Liverpool the first teams to capitalize.
The Premier League resumes after a two-week international break with Arsenal, rejuvenated by the signing of Germany playmaker Mesut Ozil, top of the standings on goal difference from Liverpool after seven matches.
It's early days but United is languishing in mid-table after three losses and the champions could encounter more problems on Saturday when fourth-place Southampton, one of the surprises of the season so far, visits Old Trafford.
Here are five things to know about this weekend's matches in the English Premier League:
OZIL WORRY FOR ARSENAL
Arsenal will be hoping a knee injury picked up by Ozil on international duty on Tuesday doesn't stop him playing against Norwich on Saturday.
Ozil, who hobbled off late in Germany's 5-3 win over Sweden in a World Cup qualifier, has been an instant hit at Arsenal since joining for a club-record 50 million euros ($66 million) on transfer deadline day, transforming the mentality of a squad that has gone eight years without a trophy.
"He came back with a knock on the knee, but it was just a kick," Arsenal manager Arsene Wenger said. "We will have a test tomorrow (Friday) to see if he is fit enough for Saturday or not."
If only Wenger could have signed the playmaker back in 2010.
"I had been in contact with Mesut before, when he first went to Real Madrid three years ago," Wenger said this week. "I spoke to him back then on the phone, in the end he told me he wanted to go to Real Madrid, so I wished him well, but that first contact had been made. He knew that I wanted him for a long time."
STURRIDGE PARTNERSHIP BLOSSOMING
Any fears that Luis Suarez would take time to get back into his stride after serving a 10-game ban for biting an opponent have been well and truly cast aside.
The Liverpool striker has scored three goals in two matches since his return to the team from suspension and has struck up a brilliant partnership with Daniel Sturridge, who also netted in those matches against Sunderland and Crystal Palace.
The league's most feared strike combination will fancy their chances of adding to their haul on Saturday when Liverpool travels to Newcastle, whose flimsy defense has been ripped apart by Manchester City, Hull and Everton already this season.
"He's a nice guy and we have great chemistry on the field, and we get on well off it so it's good," Sturridge said.
POYET'S FIRST SUNDERLAND MATCH
By firing Paolo Di Canio after seven months in charge, Sunderland's gamble on hiring an outspoken coach with no top-flight managerial experience backfired spectacularly.
So what did the struggling northeast club do next? Hire another coach with similar credentials.
Gus Poyet's only previous job was at second-tier English club Brighton, but he has been tasked with keeping Sunderland in the Premier League after its dreadful start to the season that has left the team bottom on just one point.
"I hope I can show I can do it at this level," Poyet said upon taking charge during the international break.
Poyet's first game in charge is at Swansea on Saturday.
SAINTS GO MARCHING TO OLD TRAFFORD
Save for Man United, all the usual big teams are already occupying the top positions in the league after just two months. And then there's Southampton.
The acquisition of Italy striker Pablo Osvaldo from Roma in August was a sign that the south-coast team meant business this year, having only survived relegation by five points last season.
Southampton is in fourth place, has the best defense in the league — conceding just two goals so far — and has already won at Liverpool to end the then-leader's unbeaten start. It has done all this with core of English players in the squad at a time when home-grown talent is struggling to get a look-in more than ever before in England's top division.
Next up for the Saints is a trip to United, whose last home match saw the team trip up 2-1 to West Bromwich Albion.
Many pundits' title favorite after bringing in nearly 100 million pounds ($160 million) of talent in the offseason, Manchester City has shown the wrong kind of consistency in its opening seven games.
Sublime at home, where it has won all four of its games and scored 13 goals in the process, City is yet to win away after losing to promoted Cardiff and Aston Villa and being outplayed in a 0-0 draw at Stoke.
Defensively, Manuel Pellegrini's side has been suspect on its travels so Vincent Kompany's likely absence with a knee injury for Saturday's match at West Ham will be sorely felt.
West Ham is also coming off a shock 3-0 win at Tottenham, where Ravel Morrison's solo goal from the halfway line provided another glimpse of the young winger's talents. Some even see the former Manchester United player potentially in England's squad for next year's World Cup in Brazil.