Sporting Kansas City missed the chance to put pressure on DC United at the top of the MLS Eastern Conference as they were held to a 1-1 draw by the Philadelphia Union.

Kansas City could have taken the lead in the 11th minute when Dominic Dwyer met a corner from the right with a powerful header, but Brian Carroll was on the line to clear the ball away.

The Union responded and the home side were grateful to a great save from Andy Gruenebaum as he tipped Vincent Nogueira's powerfully-struck free kick over the bar.

Just before half time, Mikey Lopez was presented with a great opportunity to hand his side the lead as he chased a ball over the top, but his volleyed effort was saved by the legs of Zac MacMath.

In the second half, Danny Cruz produced a moment of magic to release Carroll with an inch-perfect through-ball and the midfielder fired a powerful shot at goal which was well stopped by Gruenebaum.

Sporting used the save to their advantage as they went ahead when Toni released the run of Graham Zusi into the penalty area and the midfielder slotted the ball past MacMath with a neat finish.

Zusi came within centimetres of adding a second for Kansas City minutes later as he latched on to Dwyer's clever back-heel in the box, but his effort with the outside of his foot drifted agonisingly wide of the target.

The miss was to cost the home side as Philadelphia earned a point when Brian Brown guided Raymon Gaddis's cross into the bottom corner of the net from close range.