Defending champion Rita Jeptoo of Kenya won her second consecutive Bank of America Chicago Marathon on Sunday, making her the first ever man or woman to win four straight world marathon majors.

Her unofficial time was 2:24:35. Mare Dibaba followed with a time of 2:25:37 and Florence Kiplagat with 2:25:57.

"It was very difficult [at the] start," Jeptoo said, noting she looked to her Chicago fans for support. "Everybody was looking for me, so I tried my best."

Jeptoo's 2014 campaign has already been on fire, with her winning her third Boston Marathon early in the year and becoming the first woman to defend that title since Catherine Ndereba in 2005.

Jeptoo ran her first career sub 2:20 in last year's Chicago race, the fifth fastest time in Chicago Marathon history.

Sunday's finish marks wins at two major marathons in two consecutive years.

"I'm so happy," she said.

"Rita is in the prime of her career," race director Carey Pinkowski said. "If you look at the running in Boston and the training she's done, she has some very aggressive goals. She's in great shape and is familiar with Chicago, she likes it, she's had success here and that's the formula for records."

Two years ago, Jeptoo was neck-and-neck last year with Atseda Baysa of Ethiopia for a thrilling photo finish. Baysa broke the tape in the end, just milliseconds ahead.

Last year Jeptoo got hers, breaking away from her closest competition well before the final mile.

Baysa was reportedly a late scratch from Sunday's race, but it wasn't immediately clear why she withdrew.