The English champions are under pressure off the field amid a probe by Premiership Rugby over a possible breach of domestic salary cap rules.
Saracens have also been dealing with the row sparked by Billy Vunipola liking a post from Australia’s Israel Folau that stated “hell awaits” for homosexuals.
The England No 8 was warned by both his club and the Rugby Football Union after a post of his own last week that read “man was made for woman to procreate that was the goal no?”
Vunipola was subsequently jeered by fans during Saracens’ 23-21 loss away to Bristol last weekend.
He is set to start against Munster in Coventry, with coach Mark McCall telling him to prepare for more boos.
“He has got to deal with that, and we’ve got to deal with that as a group,” said McCall. “It’s probably better to expect it to happen, and then wait and see.”
All four sides in the semi-finals are former European champions, with both Saracens and Munster having won the tournament twice.
Meanwhile, title-holders Leinster and Toulouse, who meet in Dublin on Sunday, are both four-time kings of Europe.
Saracens were beaten by Leinster in last season’s quarter-finals but McCall said that defeat had only strengthened their passion for the tournament.
“I think it made our group, after winning the two finals the two years before that, really hungry to do well this season,” said McCall. “I think this group have grown to love this competition.”
Saracens cruised into the last four with a 56-12 thrashing of Glasgow whereas Munster had a hard-fought 17-13 win over Edinburgh.
– ‘Means the world to me’ –
The Irish province have not won the tournament since 2008 and scrum-half Conor Murray is desperate to add a European title to his CV.
Boyhood Munster fan Murray, who turns 30 on Saturday, was not at his best during a disappointing Six Nations for Ireland after starring during a stellar 2018 that yielded a Grand Slam and a win over world champions New Zealand.
“I’ve been lucky with Lions tours and Six Nations wins and I wouldn’t trade them,” Murray told the Guardian. “But winning the European Cup with Munster would be unbelievable. It means the world to me.”
Murray’s Ireland half-back partner Jonathan Sexton returns for Leinster against Toulouse following a quad injury in what is set to be his first match since facing Wales on March 16.
“We’re giving Sexton the benefit of the doubt based on the calibre of player he is and his experience,” former Ireland coach Eddie O’Sullivan told the RTE Rugby Podcast. “There’s a risk in it and there’s a bigger risk for Leinster if you look at where they are coming from.”
Leinster, who have recalled several rested first-choice players, and Toulouse met twice in this season’s pool stages, winning once each.
Toulouse edged out French rivals Racing92 22-21 in a thrilling quarter-final despite being a man down for more than 50 minutes after Zach Holmes was sent off for a high tackle.
“I’m very proud of the team how we played with 14 men for most of the game,” said Toulouse captain Jerome Kaino.
Sunday’s match will be Toulouse’s first European semi-final in eight years and the French side received a boost Thursday when Joe Tekori was cleared to play after being cited for a dangerous tackle in last weekend’s Top 14 win over Clermont.
The 35-year-old Samoan lock risked being suspended but officials found he had “made his best efforts to make a regular tackle” in a challenge that left opponent Yohan Beheregaray unconscious.
Fixtures
Saturday: Saracens (ENG) v Munster (IRL), Coventry (1400 GMT)
Sunday: Leinster (IRL) v Toulouse (FRA), Dublin (1415 GMT)
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