"It was very humbling, being the top dog on the campus to coming to the league and not really playing at all," Jenkins said. "It was kind of humbling and it teaches you a lot about the game. I'm watching the game from the sideline, trying to learn things from different players."

One thing Jenkins wants to be able to do is make tough catches in traffic. With a larger frame, going across the middle should now come easier to the 6-foot receiver.

Jenkins spent the offseason working out with quarterback Colin Kaepernick in Atlanta, trying to become a better target for the 49ers signal caller.

"I was just working my butt off trying to put on some pounds, trying to gain some weight so I can be able to go across the middle," Jenkins recalled. "I was just trying to work on my overall game."

The 2013 season marks a fresh opportunity for Jenkins to make an impact. With fellow receivers Kyle Williams and Mario Manningham still recovering from injuries, Jenkins will get plenty of work throughout the OTAs.

Jenkins is also using his repetitions to learn all the receiver positions in order increase his versatility.

"I'm learning everything," Jenkins said. "I don't have any limit in anything. I'm a guy who's trying to come in and make a play, make an impact as well as on special teams. I'm learning anything and everything I can."

Despite a quiet first year on the field, Jenkins feels he's ready to bounce back in 2013.

"Learning the playbook gave me the confidence to go out there just knowing what I'm doing," Jenkins said. "I'm a lot better than I was last year around this time."