On a Slippery Day in London, Giants Hold On

The Giants, now 6-2, won their sixth game in a row by beating the winless Dolphins, 13-10. Miami, which scored its only touchdown with less than 2 minutes left in the game to add a welcome dose of suspense, fell to 0-8 under the first-year coach Cam Cameron.

But for the N.F.L. the game will long be remembered for the moment it represented, not the final score.