Rain frustrated England's bid for a series whitewash over India Thursday when play was washed out after lunch on the opening day of the fourth Test at the Oval. Openers Andrew Strauss (38 not out) and Alastair Cook (34 not out) put on 75 in an unbroken first wicket partnership against an under-strength attack when the rain which had been lurking around south London all morning finally descended. India, which relinquished its No. 1 ranking to England after being thrashed in the first three Tests in the four-match series, lost its best remaining bowler before the start of play. Left-arm pace bowler RP Singh, who had not played a Test for more than three years, replaced Praveen Kumar, who injured his ankle in the third Test at Edgbaston. Initial reports said Kumar had dropped out after injuring his right thumb in Birmingham but the Indian management issued a statement during the scheduled tea interval saying his problem was an injury to his left ankle. India's leading bowlers, left-arm pace bowler Zaheer Khan and off-spinner Harbhajan Singh, are also injured. Strauss elected to bat after winning the toss, marking the first time in the series that the opposition side has not been inserted, and England's only moment of real uncertainty before lunch came when its captain was hit on the helmet by Ishant Sharma. Strauss had made a late decision to pull a short-pitched ball off the front foot when he was on 24. Singh took the new ball and an lbw appeal against Cook was rejected when umpire Simon Taufel decided the ball was going over the stumps. The left-hander edged the next delivery through the slips to the boundary. Strauss also collected his first boundary through the slips off Sharma who bowled an accurate line and occasionally troubled the batsmen with late movement off the pitch. The rain started to fall half an hour into the lunch break and umpires called play off at 1600 GMT. Dilshan confirmed Tillakaratne Dilshan was confirmed Thursday as Sri Lanka's captain in all forms of the game for the rest of the year, the cricket board said in a statement. Dilshan, 34, had been appointed skipper on a series-to-series basis after Kumar Sangakkara stepped down following Sri Lanka's defeat in the World Cup final against India. Under Dilshan, Sri Lanka lost the Test and one-day series in England, but have enjoyed mixed results in the ongoing home contests against Australia.