Wide receiver Dante Pettis may have only had four catches for 20 yards on Sunday against the Pittsburgh Steelers, but the second-year San Francisco 49ers wideout also came away with what turned out to be the game-winning touchdown reception.

Pettis pulled in the five-yard score off a Jimmy Garoppolo-thrown pass to put the 49ers up 23-20 with just over a minute left on the game clock. The extra point made it 24-20, the defense held, and San Francisco now owns a 3-0 record for the first time in over two decades.

Many felt Pettis was in head coach Kyle Shanahan's dog house. The former second-round pick didn't see a lot of action during the first two games, but it wasn't because the coach didn't believe in his young receiver.

That's not to say that Shanahan didn't challenge Pettis to be better. He did. Well, it at least seemed like he did. Whatever the coach's intention was, it appears to have paid off.

Shanahan joined KNBR on Tuesday and discussed Pettis.

"I've been real excited with Dante his last few weeks," Shanahan said on the "Tolbert, Krueger and Brooks" show. "I mean, everyone knows that I put a little bit of pressure on him going throughout training camp, and 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, which he kind of is assuring me that I should do that more because the way he's been these last few weeks.

"He really took the challenge. I think he's been a little different in the weight room and stuff."

Most know that Pettis was set back by a minor groin injury. What you may not have known was the receiver was dealing with other issues, too.

"He had an injury in training camp where he hurt his pec," Shanahan continued. "That made it tough to lift his upper body and stuff, which he's still coming back from but my biggest thing with him is his legs and everything. I think the way he's attacked that weight room and got his leg strength back and just 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, and 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."

You can listen to the entire conversation with Shanahan below.