Utley, 34, is batting .275 with 15 home runs and 42 RBI this season and is in the final year of a seven-year, $85 million contract. The new deal would be for 2014 and '15 seasons.
Utley missed almost a month of action earlier this season due to a strained right oblique, and he has only played in 84 of the team's 113 games.
More from Fox Sports:
Such a deal seemed difficult to imagine before the start of this season. Utley, due to a variety of knee problems and right thumb surgery in 2010, averaged only 100 games the previous three years.