Springboks choose against picking late call-up Pollard for Ireland match
Pollard, 29, has replaced injured hooker Malcolm Marx in the squad with the inconsistent Manie Libbok the only recognised stand-off in the group.
Pollard scored 22 points in the Springboks' 32-12 World Cup final victory over England four years ago and had originally been left out of this squad due to a calf issue.
"He will definitely not be selected this week apart from if there are two or three injuries," Erasmus told reporters.
"He's only just joined us today.
"He must get up to speed with the intensity of our training sessions, get through them and slot in nicely.
"We've only played two games of this World Cup so I'm pretty sure somebody will press on his button and use him but not this weekend," he added.
Former Springboks head coach Erasmus has been linked with a move to the Irish Rugby Football Union as performance director replacing David Nucifora, who is stepping down after next year's Olympics.
Current Boks head coach Jacques Nienaber is heading to Dublin after the tournament to join Leinster.
Both Erasmus and Nienaber have been virtually inseparable, they were also together at Leinster's great rivals Munster in the 2016-17 season.
"I won't be following Jacques," Erasmus said.
"There's no truth in that.
"I'm not sure where that has started, I haven't chatted to them," the 50-year-old added.
Lock Eben Etzebeth missed Sunday's win over Romania after injuring his shoulder in September 10's win over Scotland.
"He reacted well last week," Springboks assistant coach Deon Davids said.
"He will be in contention for this week," he added.