With the game locked at 2-2 after 120 minutes, and high drama, it was left to the lottery of spot-kicks to decide who would advance to the final four of the tournament. Albion's top-scorer Glenn Murray missed the opening penalty before successful penalties from both sides saw the score in the shoot-out at 3-3. But the Lions' Mahlon Romeo was denied by the feet of Ryan before Dale Stephens put Brighton 4-3 ahead. Veteran Millwall forward Steve Morison and Seagulls captain Lewis Dunk then converted their spot-kicks but Jake Cooper smashed his penalty high over the bar sparking wild Brighton celebrations. On the shoot-out Ryan said: "It's been a bit of a frustrating trend where we've conceded quite a few in the league and we have high standards of ourselves as goalkeepers in our group. "When I went away to the Asian Cup I made two saves there which helped us progress through to the quarter-finals and I sort of had the same thoughts in my mind. SEE ALSO Brighton star reveals his secret behind scoring the winning penalty at Millwall | Chairman Tony Bloom hails Brighton's 'miracle' comeback at Millwall | Brighton 'keeper has the last laugh on Everton, Millwall and Australia legend | Six things we learned from Millwall v Brighton & Hove Albion | Locadia praises Brighton team-mates after Millwall fightback"I haven't saved one in the league this year so I was hoping to save them when it counted and thankfully I got one in the end today. "The boys held their nerve from the spot and we did our job and march onto the semi now." Ryan also revealed he was fully prepared for a potential shoot-out after watching clips of Millwall's penalties. The Australian added: "We take advantage of technology these days. Maybe not take advantage, but you'd be naive not to think the opposition knows you're looking. It's not rocket science. "At the end you probably cancel each other out and I think penalty takers should know goalkeepers are looking. "We're trying to gain an advantage any way we can by looking at certain clips but at the end of the day it comes down to that certain moment. "If you get the timing right it's a very nice feeling."