John Terry was sent off as Pedro inspired Chelsea to a first Premier League win of the season at West Brom.
Thibaut Courtois saved James Morrison's early penalty but Pedro, who signed from Barcelona for £21m this week, fired in before setting up Diego Costa.
Morrison then atoned for his earlier error with a crisp strike before Cesar Azpilicueta made it 3-1.
Terry saw red for a second-half foul on Salomon Rondon but Morrison's header was not enough as Chelsea hung on.
More to follow
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