Paris - Grigor Dimitrov described his coaching link-up with US legend Andre Agassi and mercurial Radek Stepanek as a "great package deal" on Sunday.
Dimitrov said that the duo have injected some much-needed "positive enthusiasm" into his rollercoaster career after needing five sets to defeat Janko Tipsarevic in the first round of Roland Garros.
Agassi, the champion at the French Open in 1999, has linked up with Bulgarian Dimitrov for Roland Garros alongside former world number four Stepanek.
The American was previously coach of world number one Novak Djokovic before their nine-month partnership ended in an acrimonious split in March 2018.
"We have a pretty special relationship. We've known each other for a crazy amount of years," said 28-year-old Dimitrov after his 6-3, 6-0, 3-6, 6-7 (4/7), 6-4 win over Tipsarevic.
"We've started to speak a little bit more and potentially try to set up the exact weeks or how many weeks we can do, but all that is in the air now a little bit.
"Him and Radek are getting along so well. So it's a great package deal."
Dimitrov, a former world number three who is currently down at 47 in the world, won the last of his eight career titles at the ATP Finals in 2017.
His Grand Slam best performance remains a semi-final run at Wimbledon in 2014.
However, he has yet to reach the second week at Roland Garros.
French Open results on Sunday, the first day of the 2019 tournament (x denotes seeded player):
Men
First round
Stefanos Tsitsipas (GRE x6) bt Maximilian Marterer (GER) 6-2, 6-2, 7-6 (7/4)
Hugo Dellien (BOL) bt Prajnesh Gunneswaran (IND) 6-1, 6-3, 6-1
Grigor Dimitrov (BUL) bt Janko Tipsarevic (SRB) 6-3, 6-0, 3-6, 6-7 (4/7), 6-4
Marin Cilic (CRO x11) bt Thomas Fabbiano (ITA) 6-3, 7-5, 6-1
Nicolas Mahut (FRA) bt Marco Cecchinato (ITA x16) 2-6, 6-7 (6/8), 6-4, 6-2, 6-4
Philipp Kohlschreiber (GER) bt Robin Haase (NED) 6-4, 6-4, 6-7 (5/7), 6-1
Leonardo Mayer (ARG) bt Jirí Veselý (CZE) 7-6 (7/3), 6-3, 6-0
Diego Schwartzman (ARG x17) bt Márton Fucsovics (HUN) 6-3, 3-6, 7-6 (9/7), 2-6, 6-2
Matteo Berrettini (ITA x29) bt Pablo Andújar (ESP) 6-7 (3/7), 6-4, 6-4, 6-2
Casper Ruud (NOR) bt Ernests Gulbis (LAT) 6-2, 7-6 (7/2), 6-0
Oscar Otte (GER) bt Malek Jaziri (TUN) 6-3, 6-1, 4-6, 6-0
Roger Federer (SUI x3) bt Lorenzo Sonego (ITA) 6-2, 6-4, 6-4
Kei Nishikori (JPN x7) bt Quentin Halys (FRA) 6-2, 6-3, 6-4
Alexei Popyrin (AUS) bt Ugo Humbert (FRA) 3-6, 6-3, 7-6 (12/10), 6-3
Laslo Djere (SRB x31) bt Albert Ramos-Vinolas(ESP) 6-3, 6-2, 7-6 (7/2)
David Goffin (BEL x27) bt Ricardas Berankis (LTU) 6-0, 6-2, 6-2
Women
First round
Sloane Stephens (USA x7) bt Misaki Doi (JPN) 6-3, 7-6 (7/4)
Sara Sorribes Tormo (ESP) bt Alison Van Uytvanck (BEL) 6-1, 5-7, 6-2
Garbine Muguruza (ESP x19) bt Taylor Townsend (USA) 5-7, 6-2, 6-2
Johanna Larsson (SWE) bt Magdalena Rybarikova (SVK) 6-3, 6-4
Kateryna Kozlova (UKR) bt Bernarda Pera (USA) 6-2, 7-6 (7/5)
Elina Svitolina (UKR x9) bt Venus Williams (USA) 6-3, 6-3
Belinda Bencic (SUI x15) bt Jessika Ponchet (FRA) 6-1, 6-4
Laura Siegemund (GER) bt Sofya Zhuk (RUS) 6-3, 6-3
Anastasia Potapova (RUS) bt Angelique Kerber (GER x5) 6-4, 6-2
Markéta Vondroušová (CZE) bt Wang Yafan (CHN) 6-4, 6-3
Petra Martic (CRO x31) bt Ons Jabeur (TUN) 6-1, 6-2
Kristina Mladenovic (FRA) bt Fiona Ferro (FRA) 6-3, 7-6 (7/3)
Kristína Kucová (SVK) bt Svetlana Kuznetsova (RUS) 6-4, 6-2
Karolína Plíšková (CZE x2) bt Madison Brengle (USA) 6-2, 6-3