INDIANAPOLIS — Nobody is likely to call Lewis Hamilton's first Formula One victory a fluke any more.

The sensational 22-year-old rookie from England not only backed it up with his second straight win, he did it by fighting off two separate challenges from Mercedes McLaren teammate and two-time world champion Fernando Alonso.

A week earlier, in Montreal, Hamilton was aided by five full-course caution flags, one of which caught his teammate on pit road and took him out of contention, relegating the Spaniard to a seventh-place finish.

Sunday, in the U.S. Grand Prix at the historic Indianapolis Motor Speedway, the safety car stayed behind the pit wall and Hamilton outdueled Alonso to gain his seventh consecutive top-three finish — a first in F1 for a rookie — and extend his points lead over his teammate to 10 points heading to the French Grand Prix in two weeks.

This is all very heady stuff for the youngster, who is the first black driver in F1 history.

"Coming into the season, being realistic, I never expected anything like this, but I hoped to do well," Hamilton said. "I hoped maybe I'd get a podium at some point. This is just insane."

The McLaren drivers finished 1-2 for the third time this season, but this time the order was reversed from Malaysia in April and last month's race at Monaco.

Hamilton started from the pole for the second straight race and Alonso tried hard to pass his less experienced teammate at the start. He darted to the outside and pulled nearly alongside Hamilton for a moment, then backed off and dived to the inside as the leaders squirted through the first two narrow turns, a sharp right-hander and then a left-hander.