A champion in Strasbourg on the eve of Roland-Garros, Krejcikova extended her current winning streak to 12 consecutive matches.
She was ranked 114 in singles when she made her first run to a Grand Slam fourth round in Paris eight months ago and is now the Roland-Garros champion -- a remarkable rise for the former doubles No.1.
>> MORE ON KREJCIKOVA'S CROWNING MOMENT HERE
Krejcikova paid tribute to her late coach Jana Novotna, who passed away after a battle with cancer at the age of 49 in November 2017.
"I cannot believe what just happened, I cannot believe that I actually won a Grand Slam," an emotional Krejcikova said on court.
"I was going through a really hard time when Jana was passing away, I was most of the time her, and I really wanted to experience this because I thought it's just going to make me really strong. Pretty much her last words were, 'Just enjoy and just try to win a Grand Slam. I know that from somewhere she's looking out for me and all of this, what happened these two weeks is because she is just looking after me probably and I just want to really thank her.
"It's amazing that I had a chance to meet her and that she was such an inspiration for me. I just really miss her but I hope she's happy right now and I'm extremely happy."