The German suffered his first loss in charge of the Blues, as the Baggies pulled off a stunning 5-2 win to snap the hosts’ 14-match unbeaten streak under their new boss.
And after taking the lead through Christian Pulisic, the Baggies rallied when Thiago Silva was sent off and entered the break ahead.
Matheus Pereira and Callum Robinson both hit doubles in the shock result for Sam Allardyce’s side, who are now seven points off Newcastle in the bid to pull off an unlikely escape from relegation.
But just days away from the first leg of their last eight tie against Porto in Seville, Tuchel has warned his players to respond after being exposed by West Brom.
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“We were not able to cope with the situation,” Tuchel told BT Sport. “I don’t know why. After the red card we couldn’t adapt, we gave away easy goals.
“What could go wrong, went wrong, we have to accept a big loss, hopefully it’s a big wake-up call, me included.
“It wasn’t his [Thiago’s] mistake, before the yellow cards, too many ball losses, even before, the yellow and red card, it was impossible for us to adapt to the situation.
“We cannot get worse. It’s not typical to concede goals like this, we usually defend, we conceded two of them. Clearly what could go wrong, went wrong. We had big chances, with the post. Clearly it wasn’t our day.
“We need the right response, it’s absolutely necessary. We have to digest this. I didn’t see it coming. We have to take our responsibilities, improve it, shake it off and do better tomorrow.”
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