West Brom moved top of the Sky Bet Championship but had to settle for a 1-1 draw against dogged Millwall at The Hawthorns.
Albion extended their unbeaten run to six games in the league but their four-match winning run ended after captain Kyle Bartley's 49th-minute header was cancelled out by on-loan Arsenal defender Daniel Ballard's header six minutes later.
The Baggies went top as previous leaders Fulham lost by a narrow 1-0 defeat at Blackpool.
A draw was a fair result with Albion winger Grady Diangana missing an early chance and striker Karlan Grant's penalty saved by Bartosz Bialkowski in the first half, while Millwall pair Jed Wallace and Sheyi Ojo were denied by goalkeeper Sam Johnstone.
The visitors spent much of the first half defending but actually created the first opening. Billy Mitchell unleashed a low effort that forced Johnstone into a diving save.
But Albion soon began to assert their authority with two chances falling to Diangana. The former West Ham winger did brilliantly to hold off Jake Cooper in a high-speed chase through the middle before dragging a low effort just wide of the far post.
Diangana's next chance was much more difficult and he failed to keep a falling volley down from the edge of the box as the ball sailed high over Bialkowski's crossbar after some head tennis in the penalty area following a long Darnell Furlong throw-in.
Millwall threatened on the break when a poor header from Semi Ajayi left Wallace in the clear, but Johnstone was off his line to palm the ball away.
There was drama right at the end of the first half when West Brom won a penalty. Diangana tumbled under what looked like faint contact from Maikel Kieftenbeld chasing a short corner.
But Grant's spot-kick was at easy height and Bialkowski guessed correct, diving to his right to palm the ball away.
Albion started the second half with purpose and took the lead four minutes after the break.
Bartley rose above Cooper to glance a header beyond Bialkowski from Conor Townsend's cross after Grant's knockback.
The Baggies' lead lasted just six minutes before Millwall drew level. Wallace crossed deep from the right and Ballard's far-post header somehow crept under the crossbar despite there being three Albion players on the line.
After a very scrappy first half, the game had really opened up.
The away side tried to catch West Brom on the break through Scott Malone, whose early cross set up Ojo, but the on-loan Liverpool forward failed to control the ball and the chance was lost.
Albion returned fire and Ajayi sent a downward header bouncing over the crossbar from Furlong's cross.
But the home side had a let-off in the 74th minute. Ajayi mis-hit a backpass to present Ojo with a one-on-one chance, but Johnstone saved his team-mate's blushes by keeping out the shot to his right.
