Ponga was in the thick of the action as his Newcastle side fell 32-30 to Melbourne in a pulsating battle at AAMI Park on Friday night.
The 28-year-old had 17 runs for 150 metres but also threw a wild pass that led to Melbourne scoring.
Alec MacDonald scooped up the loose ball and threw it on to Jahrome Hughes, with Ponga then injuring his neck as he attempted to tackle the Storm halfback and dropped to the ground clutching at the region.
Ponga stayed on the field for the remaining 35 minutes but Knights coach Justin Holbrook said post-match he was "very stiff and sore" while club medical staff said he could miss a week if he was available for team selection rather than on Origin duty.
Ponga was able to pose for a few photographs before boarding the team bus but did look hindered by the injury.
Earlier in the match, Ponga looked like he could have been in trouble as he pulled off a try-saving tackle on Melbourne's Will Warbrick.
With Warbrick over the tryline, Ponga dislodged the ball with the Storm winger claiming a shoulder charge.
Referee Ashley Klein, who sent Ponga off during the first Origin for the same offence, didn't see it that way, nor the NRL bunker, deeming it to be "all-ball".
Ponga was also involved in a scuffle with Cameron Munster, with the Storm five-eighth pushing his Queensland teammate to the ground.
An ex-Maroons player, Dane Gagai, then got involved with he and Munster wrestling on the ground.Â
Munster said he didn't hear the whistle after Ponga knocked the ball on and thought he was playing on.
"I didn't hear a whistle - sometimes you think it's a knock-on you stop," Munster told Fox Sports.
"I'm not stopping for Kalyn, he makes me look silly most of the time.
"It might not look good but at the end of the day he's not my teammate, these are my teammates (gesturing to Storm players) and I'll work hard for my teammates."
The State of Origin teams will be named on Monday June 8 with the match at the MCG on Wednesday June 17, with NSW holding the series lead after winning game one.
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