Matheus Pereira and Callum Robinson scored twice as struggling West Brom overwhelmed 10-man Chelsea and emphatically ended the 14-match unbeaten start to Thomas Tuchel’s tenure at Stamford Bridge.
The Baggies were as brilliant as the Blues, who had Thiago Silva sent off in the 29th minute, were abject.
The result moves the 19th-placed side to within seven points of 17th-placed Newcastle, and even if they do not manage the improbable and escape relegation, they will look back on this day with great pride.
Tuchel said he “did not see the second half coming”. His side took the lead through Christian Pulisic in the 27th minute, but then lost Thiago and conceded twice in first-half stoppage time before West Brom inflicted further damage after the break.
“There is no need to concede five goals when you have our quality,” he told BBC Sport. “We are all in on that – myself included.
“We could not adapt to the situation, which is a surprise as we were leading. We are normally confident enough to defend, but we were sloppy and kept making big mistakes. It’s tough to digest.
“I did not see that second half coming. We tried to give a bit of security with a back three, but we were never in a flow. We had some chances but we didn’t defend well.”