Rodgers critical after exit
Celtic boss Brendan Rodgers was critical of the performance following the Europa League exit at Zenit St Petersburg.
The visitors had gone into their second-leg tie with a single-goal advantage but were blown away as Branislav Ivanovic, Daler Kuzyaev and Aleksandr Kokorin struck for their opponents in a comprehensive 3-0 victory.
"Defensively, we lacked aggression, first-half especially," Rodgers told BBC Scotland. "We didn't close the space quickly enough. We talk about 'defending forward' and we just didn't do that well enough. And, of course, we conceded poor goals.
"We didn't have enough control in the first half in order to play forward," he added. "We didn't threaten at all, because we were too negative in our play. We weren't looking forward quickly enough and didn't get into the final third with any quality. But, to really threaten, you have to ensure you defend better."