Gregor Zabret proved the hero as Swansea City Under-23s progressed to the Premier League Cup semi-final after a dramatic shootout victory over Nottingham Forest in a game dominated by penalties.
Gary Richards and Cameron Toshack saw their side move one step closer to a third successive final in the competition as they reached the last four after a nailbiting encounter.
Swans stopper Zabret kept out four penalties in total during a tense affair at the Impact Arena in Alfreton.
Captain Adam King, sub Adnan Maric and Matthew Blake kept their cool from the penalty spot to convert their chances for the visitors, while sub Joe Coveney hit the crossbar and Zabret saved the efforts of Alex Mighten and Brennan Johnson.
It was the second time in the game that Zabret had denied Johnson, with the Slovenian saving his 15th-minute penalty.
The Swans now progress to the semi-final of a competition where they were runners-up last year while running out winners the previous year.
The Swans made three changes to their starting XI.
From the 2-0 win over defending champions Aston Villa last time out, the Swans welcomed back Tyler Reid in defence as he took the place of 16-year-old Tivonge Rushesha at right-back.
Midfielder Adam King returned to captain the team while Mason Jones-Thomas was the final change as he replaced Keiran Evans.
Despite the late heroics, it proved an encounter of few chances in Alfreton, with the penalty save proving the key factor in the first half.
It was the Swans who probed first, however, with Brandon Cooper denied close range from keeper Liam Bossin following a melee in the box. From the loose, Ben Cabango could only divert his effort over the crossbar from 12 yards.
The next big talking point came from 12 yards after 15 minutes and again involved Cabango.
The centre-back challenged Yassine En Neyah in the box and the striker hit the deck and was rightly awarded the spotkick.
But Zabret kept the Swans on level terms with a save low down to deny Johnson.
That was it for the first half, with neither team able to break the deadlock.
After the break, the Swans made a decent start as Tom Price’s 25-yard left-footed drive looked destined for the top corner only for Bossin to dive across his goal to tip it wide.
The visitors lost Oli Cooper on the hour mark as injury saw him replaced by Adnan Maric.
The game continued to see both sides cancel each other out, and it took a fantastic reflex save from Zabret to save Blake’s blushes after the keeper padded his volleyed clearance over the crossbar.
Then, at the other end, Bossin rose highest to clear a dangerous Kees de Boer corner while under pressure from Brandon Cooper.
Price was at it again late on as the midfielder fired another 25-yard rocket which Bossin again had to produce a top-class save to deny him. From the resulting corner, the Forest stopper gathered on his own line with Cabango lurking.
That meant the tie went into extra-time, with 30 minutes left for both sides to press their claim for a place in the semi-final.
The Swans again went close in the sixth minute of extra-time as Blake’s dangerous free-kick made its way into the box but Jordon Garrick could only make a slight contact before Bossin collected on his own goal line.
Then, after sub Maric drove high and wide from 30 yards, the game entered a shootout.
And up stepped Zabret, who saved two and watched one of Forest’s spot-kicks hit the crossbar as King, Maric and Blake converted their chances to send the Swans through.
Nottingham Forest U23s: Liam Bossin, Mallique Spooner, Danny Preston (Kieran Hayes, 50), Liam Bridcutt (capt), Jayden Richardson, Ethan Stewart, Jake Taylor (Joe Coveney, 105), Brennan Johnson, Yassine En Neyah, Jamie Ward (Alex Mighten, 67), Arvin Appiah.
Subs: Kostas Megaritis, Jordan Wright.
Swans U23s: Gregor Zabret, Tyler Reid (Tivonge Rushesha,ht), Matthew Blake, Kees de Boer, Ben Cabango, Brandon Cooper, Tom Price, Adam King (capt), Jordon Garrick (Marco Dulca, 105), Oli Cooper (Adnan Marić, 60), Mason Jones-Thomas.
Subs: Josh Gould, Jack Withers.