Brentford beat Rotherham 5-1 to climb to the top of the Championship table, while West Bromwich Albion suffer defeat to Bolton Wanderers on the opening day.
Brentford are the early pacesetters in the Championship thanks to an emphatic 5-1 victory at home to newly-promoted Rotherham United.
The Bees were two goals to the good at the interval through Neal Maupay and Sergi Canos efforts, while Ollie Watkins and Lewis Macleod registered after the restart, either side of Maupay's second.
Wigan Athletic fared better on their return to the second tier, as they dug deep to claim a 3-2 victory over Sheffield Wednesday at the DW Stadium.
A couple of Michael Jacobs goals had given the Latics the lead at the break, and they went on to secure the win to join four other sides on maximum points.
Another of last season's promoted League One outfits in Bolton Wanderers were also victorious, with Yanic Wildschut scoring a late goal to seal a surprise 2-1 win away at West Bromwich Albion.
Possible promotion dark horses Preston North End were 1-0 winners at home to Queens Park Rangers, meanwhile - Alan Browne netting the only goal at Deepdale five minutes into the second half.
Elsewhere, Ipswich Town and Blackburn Rovers played out an entertaining 2-2 draw in East Anglia, while Middlesbrough recovered from two goals down to snatch a draw by the same scoreline at Millwall.
The other matches to take place on the first Saturday of the season saw Nottingham Forest snatch a 1-1 draw at Bristol City and Norwich City play out a 2-2 draw away to Birmingham City.
Results in full: Birmingham 2-2 Norwich, Brentford 5-1 Rotherham, Bristol City 1-1 Forest, Ipswich 2-2 Blackburn, Millwall 2-2 Boro, Preston 1-0 QPR, West Brom 1-2 Bolton, Wigan 3-2 Sheff Weds
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