Edelman spent his first four seasons in the league primarily backing up slot receiver Wes Welker, to whom he was often compared as the two have a similar physique and playing style. During those seasons, he primarily played as a returner, only seeing the field on offense when the highly productive Welker was injured. Welker left the team after the 2012 season, and Edelman seamlessly moved in to his slot receiver role, becoming one of the main targets (alongside Rob Gronkowski) for Tom Brady, averaging more than 6 catches per game. He was sidelined with an ACL injury for the entire 2017 season, and served a four-game suspension in 2018 for the use of performance-enhancing substances/drugs (PED).
Edelman is one of the most productive receivers in post-season history, ranking second overall (behind Jerry Rice) in both post-season receiving yards and post-season receptions. He has played in four Super Bowl games (XLVI, XLIX, LI, and LIII). In each of the last three (all Patriots wins), he led all wide receivers in receiving yards, culminating in an MVP-earning performance in Super Bowl LIII when he had 10 catches for 141 yards receiving, more than half of his team's total receiving yardage. He holds two Super Bowl records: career punt returns (8) and first-half receptions in a single game (7). Edelman is the first Jewish football player to have received the Super Bowl Most Valuable Player (MVP) Award. His MVP Award drew criticisms as it was given the same season he was suspended for using PED.