Lee Novak scored twice in the opening 20 minutes and Chris Burke added another to earn Birmingham City a 3-0 half-time lead over Blackburn Rovers at Ewood Park.
The ex-Huddersfield Town winger was in the right place at the right time to put the Blues ahead on 12 minutes when he tapped in from Dan Burn's layoff.
His second was much more spectacular as he found the top corner with a 30-yard drive, and he could have completed a first-half hat-trick when his header was deflected behind.
Nicola Zigic also came close as Birmingham applied pressure which was rewarded when Burke increased their cushion further by pouncing on a defensive mix-up between Grant Hanley and Simon Eastwood.
Birmingham appeared certain to stretch their unbeaten run to nine games, but Jordan Rhodes nearly gave Blackburn something to hold onto at the break when he struck the post with a shot from the right edge of the area.