2009 season:
Bock experienced a tougher year than his All-Australian 2008 season. An off field misdemeanor cost Bock his place in the side for round three but he returned to his best with a number of dominant performances at centre half-back, including winning the Showdown Medal in round 17 gathering 27 possessions, seven marks and a goal. A heel injury cost him the last four games of the minor round and despite a return to training during the finals he was unable to regain full fitness. His last game of the season was his 100th AFL game in round 18 against Geelong. Bock reflected on his difficult start to the year but believes what came out of it had a positive effect.
"I was training by myself sometimes to get the work done around the full-time course, which ran for three or four days a week, and then had to get myself up to play on the weekend,” Bock said. “It was draining mentally, but it was something I had to do and I took a lot of positives out of doing the program. I learned a lot about myself and about ways to manage the issues that occurred. “I’m really keen to keep playing good football and contribute to the club that way. I just want to show the playing group I’m pretty keen to make amends.”
In total Bock played 14 games in 2009 and gathered 195 kicks, 148 handballs, 101 marks and averaged 24 possessions a game.

David Noble’s 2009 review:
“Whether or not Nathan would’ve made a difference in that last game, who knows, but he was certainly an integral part of our backline. His offensive game really stood out and he’s going to be a key in our ability to take some more steps up the AFL ladder next year. He had a terrific year up until he was sidelined with injury and he also did well to play under sufferance for a couple of weeks prior to that.”

Career:
Bock was recruited from Woodville-West Torrens, where he showed some promise on debut in 2001 but was overlooked at the national draft. His AFL career took time to evolve and he did not make his debut until 2004, a year after he was listed as a rookie. But after starting 2005 in the SANFL, Bock made the most of his opportunities when promoted to play at centre half-back and he has been a first-choice player ever since. He played as a key forward in 2007 kicking 29 goals but went back to centre half back in 2008, staking his claim as the premier defender in the AFL. He earned all-Australian honours in that position and won his first Club Champion award.