The trade was announced after Chicago's 5-4 shootout win over Phoenix on Thursday night.
The 27-year-old Versteeg, a member of the Blackhawks' 2010 Stanley Cup championship team, has two goals and five assists in 18 games this season with Florida.
Versteeg had 20 goals and 24 assists in 79 regular-season games with the Blackhawks in 2009-10, then added six goals and eight assists in 22 playoff games during the team's run to the Stanley Cup. He had a career-high 22 goals and 53 points with Chicago in 2008-09.
It is really special. I had a lot of friends and family here tonight, and for my first [NHL] game in here it was great. I played here as an elementary-school player in the city championships and this was my first time back. It was a lot of fun..
— Toronto native Brandon Pirri after scoring 2 goals for Panthers in win at Maple Leafs on Thursday