Here are five things we learnt:
Leicester left in the starting blocks
Leicester's players cannot say they were not warned as the champions lick their wounds after Saturday's embarrassing 2-1 defeat at crisis club Hull City. Foxes manager Claudio Ranieri had said there was more chance of aliens landing in London than there was of Leicester mounting a successful defence of the Premier League title they had won so unexpectedly last season. His message proved on the money as Hull, under caretaker management and with only 13 fit senior players, kicked off the new top-flight season in stunning style. Everywhere Ranieri looked there were problems as Jamie Vardy, so prolific last season, missed chances and captain Wes Morgan creaked alarmingly in defence. The energy and power of N'Golo Kante, the driving force of the title triumph who has since joined Chelsea, was badly missed in midfield.
Guardiola’s City revolution will take time
Pep Guardiola made his presence felt in his first league game as Manchester City manager against Sunderland, notably benching goalkeeper Joe Hart in favour of Willy Caballero. He set his team out in a 4-1-4-1 formation that morphed into a 3-2-4-1 system when City had the ball; Fernandinho dropping back between the centre-backs from his holding role and full-backs Bacary Sagna and Gael Clichy stepping up into central midfield. The home side monopolised possession, seeing 77 percent of the ball, but nonetheless struggled to create chances. City were punished when Jermain Defoe cancelled out Sergio Aguero's opener and needed an 87th-minute own goal from Sunderland debutant Paddy McNair to prevail. Guardiola said his players needed to "take more risks" in possession and it is likely to be a while before they feel fully comfortable with the team's new shape.
Arsenal could do with some defenders
Arsenal were missing Per Mertesacker, Gabriel and Laurent Koscielny for their opening game against Liverpool. It obliged manager Arsene Wenger to align 21-year-old Calum Chambers and 20-year-old new boy Rob Holding in central defence and the inexperience in his back line shone through in a chaotic 4-3 defeat. Wenger defended the pair afterwards, arguing that the defence had not been solely responsible for Liverpool's goals. But with a trip to Leicester to come next weekend, Wenger needs Koscielny to recover match fitness quickly if he is to avoid having to make an emergency move in the transfer market.
Ibrahimovic and Mourinho already in harmony
With a raucous "C'mon!" and a touchline fist-pump, Jose Mourinho celebrated a winning start to his Manchester United reign as his new side won 3-1 at Bournemouth. Mourinho's introduction to United fans was his joyous jig down the Old Trafford sideline after a late Porto goal sent his team through in the Champions League 12 years ago. While the Portuguese was not quite as energetic at Bournemouth's Vitality Stadium, his reaction to Zlatan Ibrahimovic's second-half strike was instructive. Mourinho is determined to restore United to former glories after being sacked by Chelsea and the talismanic Ibrahimovic is central to his hopes of winning the title. The Swede's superb 25-yard finish, which followed goals from Juan Mata and Wayne Rooney, was therefore an encouraging sight.
Gary Lineker is a man of his word
After Leicester preserved their hold on first place in the Premier League by beating Chelsea last December, the club’s former striker Gary Lineker tweeted: “If Leicester win the @premierleague I’ll do the first MOTD (Match of the Day) of next season in just my undies.” Eight months on, he was true to his word, introducing the BBC’s flagship Match of the Day highlights programme wearing only a pair of white boxer shorts stamped with a Leicester club crest.