Fly-half Charlie Hodgson kicked six penalties, while England wing Chris Ashton scored the try.
“We showed a lot of composure and I was impressed with our ability to see out the game,” said McCall, whose side have now won two from two in the league.“We showed a lot of composure. I was impressed with our ability to see out the game.”
Elsewhere, Freddie Burns kicked 25 points as Gloucester won their first game of the season at London Irish 40-31, converting Ben Morgan and James Simpson-Daniel’s tries along with his seven penalties.
London Wasps followed the Exiles, who they play this weekend, in losing their second successive match, 30-23 to Bath.
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