With the Scarlets at Stradey and Magners League leaders Leinster to quickly follow, there is no doubt that the Ospreys are entering win-or-bust territory.
"The next three weeks will in many ways define our season and it will be a tough challenge for our squad. We are coming into the business end of the season now," said Jones.
"We go into April having to play four games, two against Heineken Cup quarter-finalists and two against Heineken semi-finalists.
"But our aim is to compete against the best teams in the best competitions and that it what we are facing."
Jones has made wholesale changes to the line-up that took the field against the Blues in the EDF Cup semi-final two weeks ago.
There is no Justin Marshall, Duncan Jones, Adam Jones, Jonathan Thomas or Filo Tiatia, but such is the depth of the squad at the Liberty Stadium, Jones is still able to parade a powerful line-up.
Blues-bound Jason Spice is handed a rare opportunity in the No. 9 jersey and partners James Hook, while Springbok Stefan Terblanche and wing Jonny Vaughton also come in behind the scrum.
In the absence of Wales loose-head Jones, Paul James will don the captain's armband with Cai Griffiths handed only a third start of the season at tight-head.
Ryan Jones slots back in at No. 8 in a new-look back row alongside Andy Lloyd and Steve Tandy, who didn't even make the 22 for the Millennium Stadium date.
Munster, meanwhile, field only three players - centre Lifiemi Mafi, lock Donncha O'Callaghan and blindside Alan Quinlan - who started in their Heineken Cup defeat to the Scarlets last weekend.
They do include former Great Britain wing Brian Carney for only his second start for the province since his arrival last month and his battle with Shane Williams should be an intriguing tussle.
But despite Munster coming over shorn of their Ireland stars, Jones expects nothing but a fervent backlash in the wake of their European exit.
"There is no good time to face an outfit as efficient as Munster, but this weekend is a particularly bad time to come up against them," said Jones.
"They were comprehensively outplayed by the Scarlets on their last visit to Wales and I am sure they will, both individually and collectively, be looking to turn things around tonight."
Commenting on his selection, he said: "To do well in the Magners League you need a strong squad that consistently performs within varying combinations.
"We have made changes from the team that beat the Blues last time out, but we have great confidence and belief in our squad and I am sure the guys selected will again show the qualities so evident at the Millennium Stadium.
"We are developing a strong, well motivated and happy group of players and we will be calling on these strengths to get us through the coming month."
Munster coach Declan Kidney admitted it will be a tough task returning to South Wales with the scars of their Stradey demise still fresh.
"Of course it's been a tough week, always is when you go out of a competition," he said.
"But what we have to do now is lift ourselves for the next challenge. This is when we find out about ourselves.
"We have to park that (Heineken Cup defeat) now.
"There will an opportunity to revisit it and see what we need to correct in the future.
"We can't do anything in the short term now about what happened last weekend but we do have control over what happens tonight and that's what we must focus on."