Complex sentence: Requiring surgery, Gagner was sidelined for the remainder of the 2010--11 season, as well as one month into the following campaign, making his return to the Oilers lineup on October 22,2011.
Split into simpler sentences: Requiring surgery, Gagner was sidelined for the remainder of the 2010--11 season, as well as one month into the following campaign. Gagner made his return to the Oilers lineup on October 22,2011.