2011 Boston Marathon Elite Race

Men's race winner Geoffrey Mutai raises his trophy. (credit: Mo Tate/CBS)

115th Boston Marathon

The men's wheelchair competitors approach the finish line. (credit: Mo Tate/CBS)

115th Boston Marathon

Masazumi Soejima wins the men's wheelchair race. (credit: Mo Tate/CBS)

115th Boston Marathon

Wakako Tsuchida receives her award after winning the women's wheelchair division of the Boston Marathon. (credit: Mo Tate/CBS)

115th Boston Marathon

Boston Marathon legend Jean Driscoll hugs Wakako Tsuchida after Tsuchida won the women's wheelchair division. (credit: Mo Tate/CBS)

115th Boston Marathon

Wakako Tsuchida celebrates her win. (credit: Mo Tate/CBS)

115th Boston Marathon

A wheelchair athlete is about to cross the finish line. (credit: Mo Tate/CBS)

115th Boston Marathon

Just a few feet separated first and second place in the women's race. (credit: Mo Tate/CBS)

115th Boston Marathon

The elite women approach the finish line. (credit: Mo Tate/CBS)

115th Boston Marathon

Caroline Kilel wins the 115th Boston Marathon. (credit: Mo Tate/CBS)

115th Boston Marathon

Women's marathon winner Caroline Kilel collapsed just moments after crossing the finish line. (credit: Mo Tate/CBS)

115th Boston Marathon

Marathon winner Caroline Kilel had a hard time getting up after crossing the finish line. (credit: Mo Tate/CBS)

115th Boston Marathon

Caroline Kilel was in an all out footrace to the finish line. (credit: Mo Tate/CBS)

115th Boston Marathon

Caroline Kilel collapses after she wins the Boston Marathon. (credit: Mo Tate/CBS)

115th Boston Marathon

The elite men approach the finish line. (credit: Mo Tate/CBS)

115th Boston Marathon

Caroline Kilel receives her awards after winning the Boston Marathon. (credit: Mo Tate/CBS)

115th Boston Marathon

Geoffrey Mutai and Caroline Kilel greet each other after each winning the Boston Marathon. (credit: Mo Tate/CBS)

115th Boston Marathon

Geoffrey Mutai celebrates his win. (credit: Mo Tate/CBS)

115th Boston Marathon

115th Boston Marathon

115th Boston Marathon

115th Boston Marathon

115th Boston Marathon

115th Boston Marathon

American Ryan Hall ran with the lead pack for most of the race.

115th Boston Marathon

Ryan Hall enjoys the attention in Wellesley.

115th Boston Marathon

American Ryan Hall ran with the lead pack for most of the race.

115th Boston Marathon

115th Boston Marathon

115th Boston Marathon

115th Boston Marathon

Kenya's Geoffrey Mutai won the 115th Boston Marathon in unofficial World Record time of 2:22:36. (Credit: WBZ/Rick Macomber)

115th Boston Marathon

115th Boston Marathon

115th Boston Marathon

115th Boston Marathon

On the Women's side - Kim Smith, who trains in Rhode Island and is from New Zealand, pulled out to an early lead.

115th Boston Marathon

115th Boston Marathon

After the halfway mark, Smith grabbed her leg. She ran for several more miles before pulling out due to injury.

115th Boston Marathon

115th Boston Marathon

Amiercan Desiree Davila challenged Caroline Kilel of Kenya right down to the wire in 2011. (WBZ-TV)