Hertha responded well but both Dodi Lukebakio and Matheus Cunha squandered promising opportunities.
"We know that nobody can ignore the importance of Paolo, but we have to try replace him and the national team has responded," Gareca told reporters in a virtual press conference.
After the restart, Desna took control and should have restored parity in the opening stages of the half as Guilavogui blocked Vladislav Kalitvintsev's rebound from inside the box on the goalline.
The 23-year-old broke the deadlock in the 74th minute by thumping in a long-range effort after combining with Darlan Mendes.
Hertha's head coach Bruno Labbadia made changes and fielded Deyovaisio Zeefuik, Arne Maie and Jhon Cordoba after the restart.
Andre Villas-Boas' side beat PSG 1-0 last Sunday, ending a nine-year winless run against the old rivals, but suffered a bitter 2-0 defeat to St-Etienne on Thursday.
Bayern chairman Karl-Heinz Rummenigge announced the club is taking all possible actions to avoid infection among fans "as we don't want to increase the cases we already have in Munich."
Elsewhere, Osasuna central defender Aridane Hernandez has a muscle injury and will miss their return to their remodeled El Sadar Stadium to take on Levante, while both Eibar and Athletic Club look for their first win of the season in their rescheduled lunchtime kickoff.
SUZHOU, China, Sept. 22 (Xinhua) -- With a wonder goal from Marcelo Cirino, Chongqing Lifan beat Wuhan Zall 1-0 in the 12th round of the Chinese Super League (CSL) here on Tuesday.
DOHA, Sept. 23 (Xinhua) -- Esteghlal FC have cruised into the 2020 AFC Champions League Round of 16 with a comfortable 3-0 victory over Group A leader Al Ahli Saudi FC in matchday six on Wednesday.
The visitors from the Ukraine grew in confidence but the dismissal of Joonas Tamm, who saw his second yellow card for repeated foul play at the hour mark, changed proceedings on the pitch.