Dango Ouattara's attempted Panenka penalty proved costly as West Ham reached the quarter-finals of the FA Cup with a 5-3 shoot-out win over Brentford at London Stadium.
After Jarrod Bowen and Igor Thiago both netted twice in normal time, the teams could not be separated after 120 minutes, with penalties required to see who would progress.
Ouattara's dinked effort was comfortably gathered by Areola, as Konstantinos Mavropanos rifled home the winning spot-kick as the Hammers stayed perfect in the shoot-out.
An end-to-end opening saw West Ham open the scoring in the 19th minute when Bowen flicked the ball past Caoimhin Kelleher from close range after Mateus Fernandes' cross was inadvertently laid into his path by Kristoffer Ajer.
However, Brentford hit back nine minutes later through Thiago, who diverted James Collins' header into the net, with the goal surviving a VAR review for a potential handball against the Brazilian.
But West Ham captain Bowen restored his team's lead from the penalty spot after Michael Kayode tangled with Adama Traore inside the box, with the technology needed again to give the decision after referee Andy Madley initially waved away the hosts' protests.
And just as though West Ham thought they were heading into the last eight, Brentford were awarded a spot-kick of their own when Kayode was pushed in the back by Crysencio Summerville, with Thiago making no mistake from 12 yards in the 81st minute.
Both sides had chances to win it in extra-time, but penalties would decide who would host Leeds United in the last eight. After scoring from the penalty spot in normal time, Bowen and Thiago netted the first two penalties of the shoot-out.
Valentin Castellanos then rifled home, only for Ouattara to follow up with a saved Panenka, which allowed Callum Wilson, Tomas Soucek and Mavropanos to send the Hammers through.
Data Debrief: Bowen stings the Bees once again
After losing 2-0 in their previous meeting in the Premier League in October, West Ham exacted revenge here to reach the FA Cup quarter-finals for the first time since 2015-16.
And though his brace in normal time did not get his side over the line, Bowen played his part in the win. He now has nine goals in all competitions against Brentford (seven for West Ham, two for Hull City) – three more than he has scored against any other opponent in his career.
In addition, since Brentford became a Premier League side in 2021-22, no player has more goals in all competitions against the Bees than Bowen (seven, level with Phil Foden and Mohamed Salah). He has only found the back of the net more than once in two of his last 129 games for the Hammers – both at home against Brentford.
Nuno Espirito Santo will, however, acknowledge that his side were made to work for their win, having registered an expected goals (xG) total of 2.85 from their 18 shots, compared to Brentford's 3.09 from their 17 attempts.