Steyn has answered an SOS from his club, the Bulls, who lost their first-choice fly-half Johan Goosen to a knee injury during the win over Cardiff Blues on Saturday.
The 27-year-old is now in line to feature against Mike Blair’s side in the United Rugby Championship.
Steyn has been part of the South Africa squad at the Rugby Championship but didn’t feature in the recent matches against Australia and New Zealand in Queensland.
He is used sparingly by the Springboks but still has the nous to influence games at the highest level, as he showed against the Lions in the summer when his penalty with two minutes remaining sealed a 19-16 victory in the third Test in Cape Town.
The victory meant South Africa won the series 2-1. Remarkably, Steyn also landed the kick that decided the 2009 series, the previous time the Lions toured South Africa.
Edinburgh host the Bulls in round four of the URC at the DAM Health Stadium this Saturday. The South African side are still in Cardiff but will travel to Scotland later this week.
“Morne Steyn is on his way to Wales where he will join the team as we prepare for our final tour match against Edinburgh,” said Jake White, the Bulls director of rugby.
“Johan Goosen will be on his way home for scans to determine the extent of his knee injury. We wish Johan well for his recovery.”