Ajax's Davy Klaassen celebrates reaching the final as Lyon's Corentin Tolisso, right, .is on the pitch after the second leg semi final soccer match between Olympique Lyon and Ajax in the Stade de Lyon, Decines, France, Thursday, May 11, 2017. Get the full report and reaction.
Ajax were on the back foot early in the second half, but Lyon lacked accuracy, until Ghezzal's 81st-minute deflected header gave the Parc OL hope.
But Ajax, who finished with 10 men after Nick Viergever was sent off in the finale, held firm to reach their first European final since 1996 when they lost in the Champions League.
However, Ajax will take confidence from the fact that sides that won the first home leg of a Europa League knockout tie by more than two goals are W4-D1-L1 in the return since 2014/15.
A dejected Lyon were handed a lifeline just prior to the interval, though - Lacazette thumping home from the penalty spot after going down under pressure from Matthijs De Ligt.
In the last round, the Belgian international's introduction off the bench changed the game, as he inspired the Red Devils' extra-time win over Anderlecht - the opposition defence couldn't cope with the star's formidable physicality in the final third.
Lyons are understandably favorite for this match, and Lyons are expected to become out as victorious tonight game, Even though Ajax end up in losing they will be winning this war tonight.
Maxwel Cornet nearly forced extra time with a shot which flew inches wide of the far post in the final minute, but a clearly rattled Ajax managed to hold on.
In the end, it was a victory that had the hallmarks of a classic Jose Mourinho success rather than the type Man United fans became accustomed to during numerous greatest moments of the Alex Ferguson era.
"Two minutes before the break, everything went wrong. I want to get better and score more goals". Of course wins help to win so we want that.
"Over the two legs, we deserve to go through", Bosz - whose side will face Manchester United in Stockholm on May 24 - told RTL. "A final play is nice, but finals you play to win".
Ajax head coach Peter Bosz has called on his youthful Ajax side to make history after they progressed to the Europa League final with a thrilling 5-4 aggregate victory over Lyon.