West Ham beat Derby 3-0 on Saturday to make it back-to-back Championship wins after a sluggish start to their campaign as leaders Swansea were held 0-0 by Welsh rivals Wrexham.
Nuno Espirito Santo's Hammers took just two points from their first three games in the English second tier after their relegation from the Premier League last season.
But they have won consecutive matches for the first time since January, scoring seven goals in wins against Wolves and Derby, to boost their promotion push.
Joel Piroe scored early at the London Stadium but the home side had to wait until late in the game before making the game safe with goals from substitutes Edvin Austbo and Mohamadou Kante.
"It took some time, being resilient, staying in the game and waiting for the right moments, but it's positive managing the game," Nuno told the BBC.
"And when we had space, we did well to kill the game."
Swansea sit just one point ahead of a pack of five teams on 10 points after extending their unbeaten start despite failing to break down Wrexham.
Will Lankshear's seventh goal in as many matches in all competitions gave Middlesbrough a 1-0 victory against previously unbeaten QPR to climb into second.
The striker has impressed since his move from Tottenham in July and his predatory first-half finish earned all three points at Loftus Road.
Head coach Kim Hellberg hailed a "big" win.
"At the end, the game showed every side of what we can do," said Hellberg. "The first 65 minutes was brilliant. We had four massive chances to kill the game off.
"You always have the worry when you don't score but we defended very good, credit to the defenders."
West Brom neat Watford 1-0 and Bristol City stunned Burnley with two late goals at Turf Moor to also move within one pont of the leaders.
Southampton conceded late to draw 1-1 at Lincoln and fall seven points off the top after they began the campaign with a four-point deduction for spying on play-off opponents Middlesbrough at the end of last season.