The Cowboys' star receiver made a couple of first-half errors, one of which he looked certain to claim in his stride for a touchdown from an excellent deep ball from Cooper Rush, only for it to slip through his grasp.
But Lamb more than atoned by making a sensational one-handed grab for a touchdown with 8:30 to play.
It was the icing on the cake of an 89-yard drive, in which Rush – standing in again for the injured Dak Prescott – found Lamb on four occasions.
"It [the dropped pass] was a situation I had to deal with on my own. Obviously I’m the one that dropped the ball for the guys," Lamb said after the game.
"So knowing that I had to make this up in the back end of the game, I just wanted to step up.
"I was willing to do anything to make up for a touchdown potentially that I left in the first quarter. It was tough. It was a tough one, but I'm happy we came out victorious."
Lamb finished the game with eight catches for 87 yards but conceded there were frustrations from his earlier mistakes.
"It was very frustrating. Honestly, just because I practice all week, all offseason just on focusing in on the ball, and I let that one slip away," he added.
"It was tough. Partially because, like I said, all the hard work I put in just for one play away, I let it slip."
Ezekiel Elliot's one-yard touchdown had earlier levelled the game, and Lamb – now the undisputed number one receiver in the team after Amari Cooper was traded to the Cleveland Browns – felt like his winning contribution was a breakthrough moment.
"Most definitely [it was a breakthrough moment]," Lamb said.
"I appreciate Kel [offensive coordinator Kellen Moore] for trusting in me, all the guys believing in my ability.
"You know, it was a tough third quarter. I kept thinking about it. All the guys kept preaching to me, 'Let it go. Let it go. We still got more game left.'
"And fourth quarter when I kept hearing my number being called I knew it was my opportunity again, so I had to step up.
"It's gonna have its ebbs and flows. It's all about being consistent. Staying positive. Everything's not going to go my way. And when it does, it's going to go big."
Stand-in quarterback Rush played in back-to-back NFL games for the first time in his career with Prescott still sidelined by a hand injury sustained in week one against the Tampa Bay Buccaneers.
For Rush, the focus is on the team and not any potential battle for a starting berth.
"I want to keep winning, as long as I'm in there let's keep winning," he said post-game.
"Trust each other both sides of the ball [and] we'll be alright."