Conner Mantz set the American marathon record in Chicago last year, but he won't compete this time. Instead, Charles Hicks, Clayton Young, and Vinny Mauri aim for the record. Hicks's Boston time of 2:04:35 is faster than Mantz's record.

Emily Sisson's women's record of 2:18:29 is harder to beat. The pace set for the leaders will influence the race. Mantz's record pace was 4:45 per mile. Clayton Young aims for the record despite a hamstring injury. Read more culture coverage.

Vinny Mauri, who ran 2:05:54 in his first marathon, plans to 'swing for the fences'. Hicks wants to be the first American to break the record. Galen Rupp and others are also in the race, but the weather may affect times. Related: Chicago Marathon Faces Less-Than-Ideal Conditions.

This original Runner World brief is based on reporting from Marathon Handbook. Visit the source for its complete reporting, context and any later corrections.