Michalek's first two NHL games were memorable for very different reasons.

The forward scored a goal for the San Jose Sharks in his NHL debut Oct. 9, 2003, against the Edmonton Oilers. Two days later in his second League game, he tore the anterior cruciate ligament in his right knee and was sidelined for months. He then reinjured the knee Feb. 7, 2004, while with Cleveland of the American Hockey League forcing him to miss the rest of the season.

Michalek, selected by the Sharks with the No. 6 pick in the 2003 NHL Draft, returned to the NHL for 2005-06, the first of four productive seasons for San Jose. He scored 20 goals in each of his final three seasons with the Sharks.

On Sept. 12, 2009, the Sharks traded Michalek, Jonathan Cheechoo and a 2010 second-round draft pick to the Ottawa Senators for Dany Heatley and a 2010 fifth-round pick.

Michalek continued his consistent scoring with the Senators. He got his first NHL hat trick Oct. 15, 2009, against the Tampa Bay Lightning, led the Senators with four shorthanded goals in 2010-11 and reached 30 goals for the first time (35) in his NHL career in 2011-12.

On Feb. 9, 2016, Ottawa traded Michalek, Colin Greening, Tobias Lindberg and Jared Cowen for Dion Phaneuf, Matt Frattin, Casey Bailey, Ryan Rupert and Cody Donaghey. 

On Jan. 31, 2015, Michalek and his brother Zbynek, who was playing for the Arizona Coyotes, each scored a goal in the game, a 7-2 Senators victory.