The 18-year-old, who spent most of the second half on the sidelines, was thrown back into the match with five minutes to go and slotted the winning kick in the penultimate minute to secure a 35-34 victory.

Walker's stunning play denied the Titans a slice of rugby league history after they'd come back from a 26-point deficit early in the second half to take a four-point lead inside the final 10 minutes.

"It was awesome. You sort of dream about it as a young fella, kicking a field goal in an NRL game," Walker said.

"That was the first one, the first one I've kicked. It's pretty crazy.

"It was an awesome feeling once it went through.

"Any grade. First attempt."

Walker had earlier played a key role in the Roosters charging to a dominant 30-6 lead, setting up two four-pointers and scoring one himself as the visitors ran riot at CBUS Super Stadium despite the late withdrawal of NSW Origin captain James Tedesco.

When Walker went off after 50 minutes after his right shoulder was driven into the turf heavily in a two-man tackle, the match took a dramatic turn.

Titans co-captain Jamal Fogarty started a remarkable comeback when he made the most of a trainer in the Roosters' defensive line to break clear from a quick tap off a penalty.

When Ben Marschke was sin-binned moments later for a late high-shot on Fogarty the game then went into overdrive.

Tyrone Peachey, Brian Kelly and Tino Fa'asuamaleaui all scored tries while Marschke was off the field to reduce the margin to just two points.

In the 72nd minute, Kevin Proctor charged on to a grubber kick to put the Titans ahead and spark wild celebrations.

That forced Roosters coach Trent Robinson to send Walker back on the field and his introduction paid immediate dividends when Matt Ikuvalu's acrobatic finish levelled the scores at 34-all.

Walker then missed a potentially match-winning conversion attempt from the sideline but had no qualms about taking the field goal shot minutes later when the Roosters pounced on a Fogarty handling error.

Titans coach Justin Holbrook was left gutted after his team nearly matched North Queensland's record 26-point comeback against Penrith in 1998 as the highest deficit-to-victory turnaround in NRL history, but ultimately came up short.

"Same feeling as last week. We tried really hard to win and fell just short. Just got to keep working and try to turn those close ones into wins," Holbrook said.

As well as Marschke, New Zealand international Jared Waerea-Hargreaves and Angus Crichton were both placed on report for high tackles while Isaac Liu was also placed on report for a first-half crusher tackle on Fa'asuamaleaui.

For the Titans, Proctor was placed on report for a first-half high shot on Manu.

Australian Associated Press