Suljovic enjoyed one of the most memorable days of his career as he defeated both Gary Anderson and Peter Wright to become the first player to book a last four spot in Cardiff on his Champions League debut.
The Austrian stormed into a 6-0 lead in his opener against two-time World Champion Anderson, with the Scot claiming three legs out of four in mid-match before Suljovic landed a brilliant 157 checkout as he closed out a 10-3 success.
He then returned to the stage in the evening session to defeat UK Open champion Wright 10-8, averaging 102.77 as he claimed his second win of the day to seal his semi-final berth.
Suljovic took out an early 105 finish to lead 3-2, and then won three in a row to move 6-3 up before defying Wright's fightback - as a 144 checkout levelled at eight-all - to hold his nerve in taking victory.
"I'm so happy," said Suljovic. "I played well today and to beat Gary Anderson and Peter Wright is a big moment in my career.
"I played a very focused game against Peter Wright but first to ten legs is a good format and I was concentrated. It's a long tournament but anything could happen on Sunday - I'm just a normal player but I'm playing well."
Wright and Anderson now face a shoot-out on Sunday afternoon to determine who joins Suljovic in the semi-finals from Group B, after both claimed wins over Dave Chisnall to eliminate the world number six.
Wright was a 10-5 winner in the tournament's opening fixture as the world number three averaged over 101 and hit six 180s in a strong performance.
Anderson later also averaged over 101 as he defeated the St Helens man 10-7 to get his challenge back on track, with Chisnall never able to level after falling 3-1 down early on before the Scot sealed victory with a 124 bull finish.
Group A is heading for a dramatic conclusion on Sunday afternoon, with reigning champion Phil Taylor claiming victories over Adrian Lewis and Raymond van Barneveld on Saturday to put one foot into the semi-finals.
Taylor defied finishes of 140 and 104 from Lewis as he came from 7-5 down to claim a 10-7 win over his Stoke rival in their Motorpoint Arena opener.
The 16-time World Champion also had to hit back from behind against Van Barneveld, with a 120 checkout levelling in leg eight before he won four of the game's final legs to complete a 10-6 triumph.
Taylor, though, could still be knocked out on Sunday afternoon should he be defeated by Van Gerwen in their final group game - with all four players in Group A still able to qualify for the semi-finals.
"I've done well today," said Taylor. "To win two games today in a group with Adrian, Barney and Michael is unbelievable and I want to carry it on tomorrow when I play Michael.
"I'm really looking forward to my next game. It's a big day on Sunday but I'm only focusing on the game against Michael at the moment."
Van Gerwen was defeated 10-5 by Van Barneveld in their opening fixture, as the five-time World Champion took out finishes of 120, 136 and 130 on his way to victory.
However, the reigning World Champion and world number one bounced back with a 10-4 win in his evening session match with Lewis, who landed an early 170 finish but saw Van Gerwen pull clear from 4-3 to seal a key win.
"I had to bounce back because otherwise I was out of the tournament, and I'm glad I did that," said Van Gerwen. "I can't really explain the first loss - things like that happen - but I played well tonight.
"I missed too many chances against Raymond but I was a lot more comfortable against Adrian, who wasn't close to his best form.
"It will be really difficult against Phil and I need to make sure I win and show everyone what I can do. Tomorrow is a totally different day but I will prepare myself because it will be tough.
"I'm looking forward to it. It's a long tournament and I want to win it, but I think I'm in a lovely position at the moment."
The results mean that there are two scenarios where there could be a three-player nine-dart shoot-out on stage to determine which players progress from Group A.
Wins by a 10-7 scoreline for Van Barneveld against Lewis and Van Gerwen against Taylor would leave the two Dutchmen and Taylor tied on four points and +4 leg difference, meaning that two players would progress from the nine-dart shoot-out.
A 10-5 win for Lewis over Van Barneveld, coupled with a 10-5 win for Taylor against Van Gerwen would see Taylor qualify automatically with his three rivals then facing a nine-dart shoot-out for the second semi-final spot.
Taylor, though, would qualify for the semi-finals if he wins eight legs against Van Gerwen as the 57-year-old seeks to successfully defend his title in the £250,000 BBC-televised tournament.
Sunday sees the final group games take place in the afternoon session, with the event culminating with the semi-finals and final in the evening session.
Tickets are available at the Motorpoint Arena Box Office on the day.
Unibet Champions League of Darts
Saturday September 16
First Group Matches
Peter Wright 10-5 Dave Chisnall (B)
Mensur Suljovic 10-3 Gary Anderson (B)
Phil Taylor 10-7 Adrian Lewis (A)
Raymond van Barneveld 10-5 Michael van Gerwen (A)
Second Group Matches
Gary Anderson 10-7 Dave Chisnall
Peter Wright 8-10 Mensur Suljovic
Phil Taylor 10-6 Raymond van Barneveld
Michael van Gerwen 10-4 Adrian Lewis
Sunday September 17
Afternoon Session (1pm)
Final Group Matches
Dave Chisnall v Mensur Suljovic
Gary Anderson v Peter Wright
Adrian Lewis v Raymond van Barneveld
Michael van Gerwen v Phil Taylor
Evening Session (6.30pm)
Raymond van Barneveld211+12
Michael van Gerwen211+12
Mensur Suljovic (Q)220+94
Two points awarded per win. No points for a defeat.
Top two players from each group progress to semi‐finals.
Any ties for Points decided by Leg Difference then:
‐ If two players are tied for Points and Leg Difference, then the winner of the group match between the players will be deemed to be the higher‐placed player.
‐ If three players are tied for Points and Leg Difference, then a nine‐dart shoot‐out will be played between the players on stage to determine placings.