Leinster booked their place in the final at Celtic Park against local side Glasgow Warriors, after a second-half comeback against Irish provincial rivals Munster – coming away 24 – 9 winners in front of a sold-out RDS.
Following the match Cullen suggested Celtic supporters should turn their back on their fellow Glaswegians and support the Irish province instead.
Cullen pointed that he believes that Glasgow Warriors fans are more likely to support Celtics’ bitter rivals, Rangers.
“Everyone in Glasgow should be supporting us,” said Cullen. “Thousands of Irish fans go over to watch Celtic play pretty much every weekend, hopefully we will have a few of those supporting us.
“Glasgow rugby players all support Rangers I’ve been told,” Cullen told the post-match press conference. “Glasgow (Warriors) are probably more Rangers supporters than Celtic ones.”
Cullen pointed out that the loss to Saracens in the final of the Heineken Champions Cup had taken a toll on his side.
“We were gutted last week. You can’t underestimate the physical and emotional toll of losing a final.”
Yesterday in form Glasgow scrumhalf Ali Price called on Warriors fans to fill the famous arena, where over 30,000 tickets have already been sold.
“We’ve all seen Celtic on European nights and it’s a brilliant stadium when it’s full,” Price told BBC Scotland.
“I’d like to think now that we’re in the final we can go a fair way in doing that and getting that sort of atmosphere. The stands are close to the pitch, right on top of the game.”
Leinster will enter their ninth championship decider looking to defend the trophy they won in Dublin in 2018, while Glasgow Warriors will attempt to reclaim the title they first won in 2015.
With a capacity of 60,832 Celtic Park is primarily a football ground, but has also hosted athletics and cycling when the ground opened in 1892.
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