It's important to note the Massachusetts native only played in three of Bostons playoff games meaning he had more down time last season. However Grzelcyk is one of the Bruins most significant free agents because he has previous experience in the game and has proven to be a top defender with his time in Boston.
The first of the three is the Chicago Blackhawks. The left side of their defense is lacking, as they have two new players who could use the wisdom of a veteran like Grzelcyk. Should the Blackhawks acquire Grzelcyk it would help them improve their powerplay, due to his puck moving abilities.
The second of the three is the San Jose Sharks. It is no secret that the Sharks have been struggling for some time now, their defense needs to improve drastically so that they can be more ruthless next season. Acquiring Grzelcyk would help them accomplish this and allow them to improve their penalty kill.
The third team who would benefit from acquiring Grzelcyk is the New York Islanders. The Islanders are another team in need of a left defenseman and since the Islanders have two UFA's who will likely be gone next season, Grzelcyk would be a great substitute.