Sydney Thunder 160-2 (17.4 overs, Khawaja 104*, Nicholls 35*) beat the Adelaide Strikers 159-7 (20 overs, Ross 47, McKay 3-44) by eight wickets
Having finished top of the group stages, the Adelaide Strikers home advantage made very little difference, as they fell in the first Big Bash semi-final to the Sydney Thunder at the Adelaide Oval.
Usman Khawaja continued his incredible form in the competition with an unbeaten knock of 104 to see the Thunder home by eight wickets, and book their spot in Sunday's final.
This was the Thunder's first ever knockout game in five Big Bash season's, whilst it is the second year on the bounce in which the Strikers have lost a home semi-final after finishing top of the pool stage.
Having finished fourth after the round-robin stages, the Thunder will again be the away side in the final, with tomorrow's semi-final between the Perth Scorchers and Melbourne Stars deciding Sunday's hosts.
Khawaja now averages 275 in the tournament this season, and is in the form of his life. With a Twenty20 World Cup just around the corner, he has given the Australian selectors a nudge as to his potential as a match winner on the biggest stage.
Strikers lose big guns during batting powerplay
After winning the toss, the Strikers chose to bat on their home surface, and did not get off to the start that they had hoped for.
The returning Mahela Jayawardene was the first batsman dismissed for just seven by Shane Watson, two deliveries after perfectly timing a six.
The Thunder continued to apply the pressure and soon had their second wicket, when Andre Russell pulled off an incredible catch to dismiss Tim Ludeman for two off the bowling of Clint McKay.
Just as Adelaide looked to be resurrecting their innings, disaster struck when their star man, Travis Head, fell to McKay just before the powerplay had ended. Head hit four boundaries in his 23 before he was caught by Ben Rohrer to silence the home crowd which was just short of 50,000.
Ross sweeps Strikers past 100
After the early wickets, the Strikers had to bed in and re-build their innings to give them a platform to launch from. That job became tougher when Brad Hodge fell for just 14 off the bowling of Chris Green, which brought Jake Lehmann to the crease to join Alex Ross.
In the 11th over with the score at 66-4, Ross got the innings going, sweeping Green for a trio of fours to get the crowd back into the game. The batsmen kept the score ticking with a pair of boundaries off Watson to take score past 100, before the former Australian test opener had Lehmann caught on the boundary for 14.
Neser and Rashid add late impetus to set winning toatal of 160
Michael Neser came to the crease, and looked to tee off from the start in the knowledge that the Strikers were well short of a winning total.
His 27 came from 16 balls and included three boundaries and a six, before he was bowled by Russell in the penultimate over.
Ross was then dismissed with four balls left in the innings for 47, with Adil Rashid taking over to hit the last three balls of the innings for 4, 4 and 6 to help the Strikers post 159 from their 20 overs.
Khawaja stuns home crowd with powerplay blitz
Chasing at eight an over looked to be a daunting task for the Thunder batsman, but within the first six overs they were already well on their way to victory.
That came thanks to some brilliantly timed shots from Khawaja who raced to 48 after just four overs. The left-hander took a real liking to Neser and Jon Holland in particular, finding the boundary with ease on numerous occassions.
The wicket of Watson for seven did not slow Khawaja who always had the Thunder in control of their chase throughout the innings.
Thunder ease home, as first place curse continues
With Khawaja steady at the crease, the result was never really in doubt. The Strikers had no answer for the in-form batsman and eventually lost by eight wickets with just short of three overs remaining.
The only other wicket they took, was that of Mike Hussey, who was adjudged to have edged Rashid behind despite replays showing that there was a large distance between bat and ball.
Henry Nicholls came to the crease at the fall of Hussey, and despite starting slowly, he soon got into his stride to finish unbeaten on 35 from 27 balls which included two big sixes.
It was left to the man-of-the-match, Khawaja, to hit the winning runs, with his superb innings of 104 not out from 59 balls seeing the Thunder home with 14 balls to spare.
Khawaja has only played three innings in this competition, and this was his second century following an unbeaten 109 against the Stars, with his other score an impressive 62 against the Melbourne Renegades.
The Thunder now await the result of tomorrow's second semi before finding out who they will face in Sunday's final, whilst the Strikers must wait another year to prove that they can win knockout matches after suffering their second straight home semi-final defeat.