NSW State of Origin lock Tyson Frizell was taken to hospital for scans on his ribs after being injured in St George Illawarra's 16-12 NRL win over the Wests Tigers.
The Blues' starting forward was hurt attempting a tackle on Tim Grant midway through the second half and played no further part in Saturday's game at ANZ Stadium.
It's understood he was taken there only as a precaution, but it would no doubt be a concern for the Blues, given Origin II is just two-and-a-half weeks away.
It's the second time Frizell has had a rib problem this year after also being injured in round six.
"Tyson Frizell copped an elbow to his pectoral in the second half against the Wests Tigers," Dragons performance manager Nathan Pickworth said on Saturday.
"As he is in a fair bit of pain, we want to send him to the hospital for an X-ray for a possible rib fracture."
In a further concern for the Blues, Josh Dugan also suffered a knee injury and required attention from trainers, but stayed on the field as the Dragons survived a late scare.
Trailing 12-2 at halftime and 16-6 with five minutes to play, the Tigers had a chance to steal it after Michael Chee-Kam crossed to narrow the margin.
But they were unable to score in a last-ditch set to suffer their fourth-straight loss.
Dragons captain Gareth Widdop had earlier scored two first-half tries on return from a five-week knee-injury layoff.
While in periods, the Dragons' attack lacked the cohesion they'd had before Widdop's injury, he had no trouble on his feet.
The Englishman opened the scoring in the 13th minute and then went 60 metres after scooping up a loose ball to have the Dragons' second try 16 minutes later.
"Our cohesion and our connection wasn't there," coach Paul McGregor said.
"But once we get that right, we sit third on the table - it's a good position halfway through the competition when I and the players feel our best footy is still ahead."
Opposition five-eighth Tuimoala Lolohea endured a difficult afternoon in his debut for the Tigers.
After only arriving earlier this week from the Warriors' reserve grade side, and without regular halfback Luke Brooks, Lolohea looked dangerous at times with ball in hand.
However, he also threw an intercept, put a kickoff out on the full and was caught out of position in the lead-up to Frizell's 50th-minute try.
"He'll get better," coach Ivan Cleary said.
"He hasn't been brought here to be the saviour.
"He looks like he's done more this week than he's done for a while - and that's just in the lead-up."
Aaron Woods ran 183 metres and James Tedesco busted 10 tackles for the 15th-placed Tigers, just three days after Origin I.
The fullback also provided a long final pass for his side's first try through Kevin Naiqama in the second half.