Birmingham made it seven straight league wins to go five points clear at the top of League One as they beat Huddersfield 1-0.
Alfie May struck his fifth goal of the season in the 63rd minute to make it Blues’ longest winning run since 1946.
But visitors Huddersfield could have been ahead after enjoying some early pressure.
Mickel Miller drove an angled shot just wide before a curling free-kick from Antony Evans was palmed away by Ryan Allsop.
City belatedly threatened through Willum Willumsson. The Iceland international’s 25-yard free kick was tipped over by Jacob Chapman then his mazy run and cross saw May head wide from a yard out.
Jay Stansfield and May both fired off target as Blues began to dominate.
Stansfield then slid a shot fractionally wide from substitute Alfons Sampsted’s cross.
May tapped home the only goal after Stansfield unselfishly squared following another Sampsted delivery.
Chapman denied substitute Emil Hansson twice and Paik Seung-ho as City hunted a deserved second goal, but May’s strike proved to be enough.