The Serbian, who is seeking his 18th grand slam title, will face Colombia's Daniel Elahi Galan in the next round.
"It's obviously an honor to play at the center court, playing against David, he is a great player. I know him very well, we're good friends, so it's not easy."
"I really wanted to give an effort here. It's my Achilles that didn't have enough to properly heal after the Open. I was able to get it somewhat better, but just looking long-term in this tournament, will I be able to get through enough matches? For me, I don't think I could," said the three-time Roland Garros winner.
The reigning Portuguese champions have offered 15 million euros (around 18 million U.S. dollars) to prise the 23-year-old away from Porto Alegre, Globo Esporte said on Wednesday.
Kenyan Peres Chepchirchir, the current half marathon record holder and Fancy Chemutai will also be in the frontline.
"I am just trying my best every single day. I am working hard in every practise to try to be better and better in every match," Nadal said,"Today was not that cold, so that's the main thing, the conditions are not that bad."
News of the transfer comes in the wake of Manchester City's 5-2 thrashing at home to Leicester City in the Premier League on Sunday afternoon. The game is the first time a side coached by Pep Guardiola has conceded five goals at home and once again served to highlight the problems at the heart of his side's defense.
Like Bayern, Borussia Dortmund might also feel comfortable, drawing Lazio, Club Brugge, and Zenit St. Petersburg in Group F.
The transfer window closes on October 5 and Koeman admitted he would like to see another central defender arrive before then.
"I really wanted to give an effort here. It's my Achilles that didn't have enough to properly heal after the [US] Open. I was able to get it somewhat better, but just looking long-term in this tournament, will I be able to get through enough matches? For me, I don't think I could," said the three-time Roland Garros champion.
"The sales of fitness equipment has been increasing. According to the Suning platform, sales of dumbbells, hula hoops and yoga mats increased by more than 300 percent over the same period of 2019," said Liu Fumin, director of the Department of Sports Economics of China General Administration of Sport.