In Havlát's third year with the club, he notched his second-consecutive 20-goal campaign with 24 goals and 59 points before helping the Senators on a 2003 playoff run to the Eastern Conference Finals.

During the 2003–04 NHL season, Ken Hitchcock made headlines once more with comments regarding a high-sticking incident with Havlát, saying that, "Somebody is going to make him eat his lunch.

Due to the 2004–05 NHL lockout, Havlát spent the entirety of the following season back in the Czech Extraliga, as well as Russian Superleague (RSL), playing for several teams.

As NHL play resumed in 2005–06, he was suspended once more early in the season on October 17, 2005, for five games following another kicking incident against Boston Bruins defenceman Hal Gill.

[5] As a result, on July 9, 2006, Havlát was traded to the Chicago Blackhawks, along with Bryan Smolinski, in a three-way deal that also involved the San Jose Sharks acquiring Mark Bell for Tom Preissing and Josh Hennessy.

On October 5, 2006, Havlát made his Blackhawks debut in outstanding fashion against the Nashville Predators by scoring two goals and two assists in an 8–6 win.

[7] He returned to the Blackhawks lineup on December 9, 2006, against the Minnesota Wild, netting two goals and an assist, albeit in a losing effort.

The season marked a turning point for the team, however, as the Blackhawks' offense was immediately bolstered by the emergence of rookies Patrick Kane and Jonathan Toews.

After three months of attempting to negotiate a long-term contract to remain with the team, Blackhawks General Manager Dale Tallon annulled previous discussions and refused to offer anything more than a one-year extension come July 1.

On March 18, one day after returning, Havlát scored the game winning goal in overtime for the Sharks in defeating the Detroit Red Wings.

[17] Three days later, on July 1, Havlát, with the ambition to redeem himself, signed as an unrestricted free agent to a one-year contract with the New Jersey Devils.

Havlat made another attempt, signing another professional tryout agreement on October 27, 2015, this time with the St. Louis Blues, earning himself a one-year contract on November 6, 2015.

[21] In August 2016, while working out with HC Kometa Brno of the Czech Extraliga, Havlát revealed that he requested the contract termination due to a groin injury, and that he intended to continue to practice with the team with the aim of returning to the NHL.