Willy Caballero replaced Kepa in the Chelsea goal, but had picked the ball out of his net three times by the 27th minute as Callum Robinson scored twice and Kyle Bartley made it 3-0.
The 64-year-old, who began his managerial career as a teenager in 1975, had previous spells as Botafogo boss in 1986, 1995, 1998 and 2001.
"He is taking his medical test and he still has to sign his contract," commented Koeman, who said that although he would "rather not talk" until the youngster had put pen to paper, "we are going to have a young full back. He will have to compete with other defenders, but he is young and has played in the Champions League and I am certain he will be very useful."
In Sunday's other fixtures, Sassuolo enjoyed a 4-1 victory over newly-promoted Spezia, while Hellas Verona edged past Udinese 1-0. Enditem
The Spaniard has won 94 matches at Roland Garros and if he can make it all the way to the final this year, there is a chance for him to equal old rival Roger Federer's record of 20 major titles in his remarkable 100th win at the clay Grand Slam.
Dortmund responded with furious attacks but Gikiewicz was alert enough to keep out promising chances from Thomas Meunier and Erling Haaland before the break.
There was last second drama as Manchester United got their first win of the season with a 3-2 victory away to Brighton on Saturday thanks to a penalty given after the final whistle.
Bayern responded well but still lacked in penetration to overcome Hoffenheim's defense. To make things worse, Hoffenheim doubled their advantage eight minutes later as Munas Dabbur capitalized on a misplaced clearance from Benjamin Pavard to beat goalkeeper Manuel Neuer into the far post corner.
"We don't know if the coach will take part in the camp but his infection won't affect the plans of the team. Moreover, the coach is able to do some things virtually," added the PZPN's spokesperson. Enditem
Ranking first in the event's preliminary heat in 2:10.25, Qin Haiyang from Shanghai didn't advance to the final as he failed to finish in the top eight in a series of physical tests - a new requirement for this year's championships.
PARIS, Sept. 29 (Xinhua) -- Czech Karolina Pliskova survived a first-round scare at the French Open on Tuesday as the second seed rallied to beat Egypt's qualifier Mayar Sherif 6-7 (9), 6-2, 6-4 to advance to second round.