Burnley, relegated from the Premier League last season, started brightly against Ipswich at Portman Road and saw an early effort from Sam Vokes come back off the woodwork.
Town, defeated in the play-off semi-finals by arch-rivals Norwich, went ahead after 66 minutes through a neat finish by Freddie Sears, who had earlier penned a contract extension with the Suffolk club.
A header from David McGoldrick (71) made sure off the points for Mick McCarthy’s side, who leapfrog Brighton.
The Seagulls saw their 100% record end with a 1-1 draw at Huddersfield.
Beram Kayal got Brighton off to a flying start when he fired home from the edge of the penalty area after just 17 seconds.
The Terriers, though, battled back and were level on 54 minutes when Jacob Butterfield’s shot beat David Stockdale at his near post.
MK Dons are third after a 1-0 home win over Bolton.
Substitute Daniel Powell had only just come on when he latched onto Samir Carruthers’ pass to fire in from the left side of the penalty in the 60th minute.
Middlesbrough were denied victory at Derby by a late equaliser from Johnny Russell (88).
Kike (16) had put the visitors ahead with his third goal in two games.
Rotherham collected their first points of the new season following a goalless draw against Preston, but only after North End defender Bailey Wright had hit the crossbar with a late header.
It was also 0-0 between Nottingham Forest and Charlton at the City Ground, where home goalkeeper Dorus de Vries produced a couple of fine saves to help earn his side a point.
At Ewood Park, Grant Hanley (88) netted a late equaliser as Blackburn drew 1-1 with Cardiff.
Joe Mason (5) gave the visitors an early lead following a poor clearance by Rovers keeper David Raya.
The home side hit the crossbar in the second half with a deflected effort from Nathan Delfouneso, before Hanley sent a header wide, but the skipper made amends with a neat finish in the closing moments.
Rovers almost snatched all three points when Shane Duffy’s header was saved by David Marshall and then had another effort hacked off the line.