Leinster remain on course for a league and European double, as they have booked their place in the Guinness PRO14 final, thanks to a second win over Munster in the space of three weeks.
Fullback Jordan Larmour is going through the return-to-play protocols after suffering a head injury during last weekend's semi-final win over Munster.
The league's top-scorer this campaign, JJ Hanrahan, had kicked Munster in front with a penalty early on with Sexton also kicking a close-range penalty in the closing stages of the first-half.More news: Cong Leader Kavitha Reddy Apologises for Attacking Actress Samyuktha Hegde
Having passed up six potential points in four minutes, Munster were driven back by Leinster when the excellent Caelan Doris forced a turnover allowing Sexton to put two scores between the sides.
Leinster also confirmed that Leavy, who hasn't played any rugby since suffering a serious knee injury previous year, will also be reviewed throughout the week.
Munster - 15 Shane Daly, 14 Andrew Conway, 13 Chris Farrell, 12 Damian de Allende, 11 Keith Earls, 10 JJ Hanrahan, 9 Conor Murray, 8 CJ Stander, 7 Jack O'Donoghue, 6 Peter O'Mahony (c), 5 Billy Holland, 4 Tadhg Beirne, 3 Stephen Archer, 2 Niall Scannell, 1 Jeremy Loughman.More news: Serena Williams survives scare to top Sloane Stephens at US Open
A second Sexton penalty penalty in the 66th minute proved the only score of the second half as Munster's season ended in disappointment.
Johhny Sexton then made Munster pay for their misses by nailing a penalty in the 68th minute extend the lead to 13-3.
Leo Cullen's men will now look forward to the challenge of facing the victor of tomorrow's game between Edinburgh and Ulster.More news: Vodafone-Idea to be known as Vi | Digital
Subs: 16 Sean Cronin, 17 Ed Byrne, 18 Michael Bent, 19 Ryan Baird, 20 Josh van der Flier, 21 Jamison Gibson-Park, 22 Ross Byrne, 23 Rory O'Loughlin.