The 19-year-old was attracting plenty of interest from a host of European clubs, with the Belgium international readily admitting his desire to move away from Stamford Bridge on a temporary basis.
Clarke, who was named as Roy Hodgson’s successor at the Hawthorns in May, is excited about helping Lukaku continue his development, with the Blues forward facing competition from Shane Long and Peter Odemwingie.
“I’m delighted to welcome Romelu to the club,” said Clarke. “He’s a strong, powerful centre-forward who is young, enthusiastic and eager to learn. He was also desperate to come here.
“Romelu had a lot of Europe’s top clubs chasing him when he joined Chelsea from Anderlecht for big money a year ago and also had several Premier League teams wanting to take him on loan this summer, so we’ve done well to get him.
“With the calibre of strikers Chelsea have got, he’s found it difficult to break into the first team at Stamford Bridge.
“But he’s had a season working at a top Premier League club and he now needs more minutes on the pitch.
“We’re more than happy for Romelu to continue his development with us.
“I am sure he will be a big help to the squad over the course of the season.”
Lukaku made just eight appearances for the Blues after completing a £18m move from Anderlecht to Chelsea last summer.
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