Unorthodox spinner Mendis played a key role in his team's stunning 55-run victory over South Africa in a rain-hit match at Centurion on Tuesday, grabbing three wickets for 30 runs.
"We have not played Mendis and some of their seam bowlers before," said Strauss, whose team were beaten 6-1 in a recent home one-day series against defending champions Australia.
"Everyone will have his own game-plan against him (Mendis). You can look at a lot of footage of him, but it is only in the middle that you can be really sure of how he bowls and what his variations are.
"It requires us to think pretty quick on our feet. There are some fundamentals you have to keep in mind against someone like him, but it is a new challenge.
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Off-spinner Muralitharan, the world's leading wicket-taker in both Tests and one-dayers, and paceman Lasith Malinga,