The Blues, who had already won Group L to reach the last 32, made 10 changes although Willian, Morata and Cesc Fabregas were among the starters.
Morata hurt his knee while shooting from Callum Hudson-Odoi’s cross late in the first half and had to be replaced by Giroud – who is now the Blues’ only fit striker.
Did Sarri need to name such a strong team for an ultimately irrelevant match in Budapest?
He even admitted before the game that it was a “difficult match to prepare for” with nothing on the line.
They named two players under 21 in their starting line-up, with another two on the bench. Arsenal named twice as many for their match in similar circumstances against Qarabag.
Chelsea only have two established strikers at the club – excluding those out on loan – and they could be down to one depending on the severity of Morata’s injury
Eden Hazard – who was rested for this game – started up front in Sunday’s 2-0 win over Manchester City and might be needed to reprise that role again.
Sunday’s Premier League trip to Brighton is the first of seven games in three weeks.
players fail to impress
Chelsea’s two teenagers had mixed fortunes with usually impressive defender Ampadu, already a senior Wales international, heading past his own goalkeeper from a flicked-on corner.
Forward Hudson-Odoi had another bright game and forced two saves from Vidi’s Adam Kovacsik.
Morata – who has only managed 10 goals in 2018 – looked short on confidence again, missing several chances before his injury.
And players like Emerson Palmieri, Ross Barkley, Ruben Loftus-Cheek and Fabregas did little to stake a place in the first-choice line-up.
Willian, the only player to keep his place from the win over City, opened the scoring with a central free-kick, which Kovacsik should have stopped.
Only 116 seconds later Vidi were level from Ampadu’s own goal.
The hosts then led when Nego, a former Charlton Athletic player, hit a brilliant volley past Willy Caballero from Georgi Milanov’s cross. He had already forced two saves from Chelsea’s back-up goalkeeper by that stage.
But substitute Giroud saved their Europa League unbeaten record with a fine free-kick that not even a defender on the post could keep out.