However, Bayern had the last laugh in the closing period after Maximilian Mittelstadt felled Lewandowski inside the box to concede a penalty. The Poland international stepped up and kept his nerves after beating Alexander Schwolow into the bottom left corner.
With the result, Union Berlin move up to third place in the standings, while Mainz stay 17th after suffering their third straight defeat of the new season.
With the pandemic under control in China, sports events like the Carnival returned, which in turn gave a further boost for people's confidence across the country to restore normal life.
Real Sociedad had a comfortable 3-0 win at home over Getafe thanks to Mikel Oyarzabal's first half penalty and goals from Mikel Merino and Portu in the 78th and 81st minutes.
"I knew she was going to be aggressive. I knew that she's playing this way. Today it worked really well for her," Halep added. "At this level, nobody surprises anybody anymore because everyone has a big level and it depends on the day that you are."
The Chinese Super League (CSL), which started the 2020 season behind closed doors in July, has been slowly opening up to a limited number of spectators last month.
Atletico Madrid at home to Villarreal is Saturday's most attractive game, with Luis Suarez likely to start in the Wanda Metropolitano as Atletico looks to improve on its flat showing away to Huesca in midweek.
Next up for Halep is another 19-year-old youngster, Iga Swiatek of Poland, whom Halep defeated in the round of 16 here last year.
Dongguan saw the national trio of Li Yueru, Yang Liwei and Huang Sijing depart to Inner Mongolia during the offseason.
However, the 35-year-old Kipchoge was dropped from the leading pack with about three kilometers to go, finishing eighth at last.
"I executed the race well despite not being fully fit. I have a hamstring injury that I want to manage when I take a break, this being the last event this season. It feels good to end the season on a winning tone, especially at home, having won the Diamond League races in Monaco and Stockholm.