Allen defeated Hawkins in a nail-biter, winning to book his third World Championship semi-final after previous appearances in 2009 and 2023.
After sealing the match, Allen couldn’t hold back a loud "Come on" and after the game, he made it clear just how much of a relief this victory was for him.
"In the end, it was just a huge sense of relief, because Barry played really well," Allen said after the match.
"Parts of the match were played at an incredible level, so this win shows where my game is at right now.
"Last night’s second session was one of the best I’ve ever been involved in.
"I was a bit nervous today, but I managed to pot some important balls."
Allen makes the better start
After an even start to the session, it was Allen who settled first. The Northern Irishman took advantage of a shaky opening from Hawkins, who missed several chances in the first two frames, making things easier for Allen.
However, the 40-year-old also struggled with his own game and only just edged the frames on the colours.
But Hawkins hit back in no time: first, he turned a half-chance into a break of 70, then followed it up with an 83.
He was extremely fortunate after 34 points in that break, missing a red but seeing another just drop into the opposite corner pocket.
Allen produces a century under immense pressure
The next two frames were shared between Allen and Hawkins. The Northern Irishman went ahead with a 59, but Hawkins levelled comfortably with two smaller breaks.
Then Allen showed his class: Hawkins barely gave the former world number one a chance, but Allen got in with a double and turned it into a superb 104 century break.
The final frame was full of drama. Hawkins led 42-0 but lost position on the black. He still attempted the pot but caught the object ball too thin.
Allen seized the opportunity with a 59 break, then played safe before the last red and even managed to snooker Hawkins.
Barry Hawkins gifts away the decider
Then things got bizarre. The 47-year-old not only escaped the snooker, but also fluked the red. The cue ball ended up tight behind the pink.
With no colour available, Hawkins saw a chance to lay a snooker with the pink, but he played the cue ball too softly, committing a foul and leaving a free ball.
Allen didn’t take advantage, allowing Hawkins to play from the position. Hawkins potted yellow but left it on.
Allen cleared the table and reached the Crucible Theatre semi-finals for the third time.
"It means a lot to me to be in the semi-finals," the Northern Irishman explained, underlining the importance of the tournament.
"The first hurdle here is always the opening round, and the next is to reach the one-table set-up. I’ve never managed that before, even though both my previous semi-finals were very close.
"I’ve won everything else, so there’s no reason why I can’t win this tournament. I’m not at my best yet, so I need to improve.
"Every year I feel I can win it, and if I play my best snooker, I have a chance – but I’m only halfway there."
Robertson holds on to his lead
Meanwhile, on the other table, Neil Robertson and John Higgins continue to put on a tactical masterclass. After 16 frames, Robertson leads 9-7.
Australian Robertson started the day with a 5-3 lead, and Higgins and Robertson shared the frames evenly, so Robertson goes into the final session this evening 9-7 ahead.
The first frame went much like most of the opening session. After more than 40 minutes, Robertson edged it, making a decisive 48 after both players had chances.
Robertson hits back after Higgins run
But then it was Higgins’ turn: first, a 51 was enough to close the gap. Then he almost went on a rampage, levelling at 6-6 with an 86 and a superb 126 total clearance.
After the interval, Higgins had another good chance, getting in at 29-0. But after just seven points, he missed the black off the spot.
Robertson took full advantage with a break of 60, ending Higgins’ run.
The Scot had another opportunity but had to leave the table after 33 points. Robertson responded with a 95 break to make it 8-6.
After a scrappy frame with no big breaks, the Australian extended his lead to 9-6, but a missed pot in the final frame of the session was punished by Higgins with an 80.
So, everything is still to play for ahead of tonight’s decider.