49ers wide receiver Dante Pettis had a redeeming performance in San Francisco's Week 3 win over the Steelers, and from the sounds of it, there might be more of that on the way.

Pettis hauled in the game-winning touchdown reception late in the fourth quarter to push the 49ers to a 3-0 record. It was the unequivocal highlight of his season thus far, after it got off to a somewhat rocky start.

Pettis was called out by 49ers head coach Kyle Shanahan in the preseason, who cited the need -- and expectation -- for more consistent production from the second-year pro. He had been hampered by a groin injury, but as Shanahan revealed Tuesday on KNBR's Tolbert, Krueger and Brooks Show, Pettis has been dealing with another injury all along that had yet to be announced publicly.

"He had an injury in training camp where he hurt his pec that made it tough to lift his upper body, which he’s still coming back from," Shanahan said.

As Pettis' pectoral injury has improved, he's been able to put in more work in the weight room, and it's starting to pay off.

"My biggest thing with him is his legs," Shanahan continued. "I think the way he’s attacked that weight room and got his leg strength back and the way he’s been working on the practice field -- it hasn’t just been this week. It’s been really these last few weeks and he’s gotten better each week.

"Now I feel he’s at where he left off last year. I think the ceiling is high for that guy, man. He can get a lot better, and we need him to."

Outside of George Kittle, Pettis arguably was San Francisco's best offensive weapon last season, which included a stretch in which he scored four touchdowns in a span of three games. Clearly, Shanahan wants Pettis not just to get back to that level, but to surpass it.

"Everyone knows that I put a little bit of pressure on him in training camp," Shanahan stated. "It wasn’t going exactly how my expectations were, which are extremely high. It’s more of a credit to Dante, because I just believe in him a lot and he wasn’t totally there, where I wanted him to be in training camp and we went a little bit hard on him.

"He’s kind of assuring me that I should do that more because of the way he’s been these last few weeks."

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Pettis heard his coach's message loud and clear, and who knows if he would have even been on the field for his game-winning touchdown reception if he hadn't. But he did, and now the 49ers are 3-0 entering their bye week, which should provide an opportunity for Pettis to get even healthier.