Cardiff City claimed a fourth successive Championship win as goals from Kion Etete and Perry Ng saw off struggling Rotherham United.
Etete headed home early in the second half before Ng swept in his first goal of the season late on to ensure Rotherham's run without an away league win stretched to 18 matches.
Cardiff have produced more fluent performances than this in the early stages of the season, but were worthy winners having shown more ambition than a Millers side who created little.
The visitors were still in the contest after Etete's opener, but could not complain when Ng scored on the rebound to end any chance of a comeback.
The Bluebirds climb into the play-off places having continued their impressive start to life under Erol Bulut.
But the outlook is much less promising for Rotherham, who remain in the bottom three having won just one of their first nine league games of the season.
Boss Matt Taylor was handed a one-match touchline ban having received a third yellow card of the season during last weekend's draw with Preston, meaning he was forced to watch this game from the Cardiff City Stadium's directors' box.
He would have been relatively happy with his team's efforts - defensively at least - during a forgettable first period in which chances were at a premium.
With Aaron Ramsey absent through injury, Cardiff looked short on attacking inspiration - though they did offer more threat than opponents whose target appeared to be a goalless draw.
Karlan Grant's surge down the left and inviting cross eventually reached Yakou Meite, but a tame shot was blocked by Tyler Blackett.
Rotherham were largely untroubled after that until just before the break, when Manolis Siopis' threaded pass teed up Ryan Wintle for a shot which was smothered by Rotherham goalkeeper Viktor Johansson.
But a Millers side with one of the worst defensive records in the division buckled when Joe Ralls fed Grant down the left and he conjured a perfect cross for Etete, who outmuscled Cohen Bramall before powering a header beyond the helpless Johansson.
With that the contest opened up a little, Cardiff centre-back Dimitrios Goutas heading across the face before Ollie Tanner - an early substitute for the injured Meite - hooked just wide at the end of a rapid counter-attack.
Rotherham's first sight of goal came just after the hour, when Siopis' heavy touch let in Oliver Rathbone only for his 20-yard drive to be well blocked by Mark McGuinness.
Arvin Appiah then cut in from the right only to shoot over before Cardiff ended the contest.
Ike Ugbo's header from fellow substitute Callum Robinson's cross was saved by Johansson, then Etete's follow-up shot was blocked.
But the ball rebounded to Ng, who became Cardiff's 11th different league goalscorer this season as he stroked in from 15 yards.
Appiah hit the crossbar with a free-kick in stoppage time, but by then Rotherham's race was run.
Cardiff City: Alnwick, Ng, McGuinness, Goutas, Collins, Siopis( Adams 87'), Wintle, Ralls © (Robinson 79'), Meite (Tanner 18'), Grant (Ugbo 87'), Etete. Subs not used: Runnarson, Romeo, Sawyers, Panzo, R Colwill.