The 22-year-old Pole cemented her standing as the very best feminine participant on the earth, significantly on clay, along with her third title in 4 years at Roland Garros.
However this was by far the toughest of her Grand Slam finals, with unseeded Czech Muchova battling again from a set and 3-0 all the way down to power a decider.
Muchova twice led by a break in that however Swiatek refused to be crushed, finally prevailing 6-2 5-7 6-4 after two hours and 46 minutes and crouching down on the clay in tears.
She is the primary lady since Justine Henin in 2007 to efficiently defend her title on the Paris clay and joins Naomi Osaka on 4 Grand Slam titles – veteran Venus Williams with seven is the one lively participant to carry extra.
Swiatek joins Osaka and Monica Seles, in the meantime, as the one ladies within the open period to win every of their first 4 Slam finals.
Muchova, a 26-year-old ranked 43, produced the efficiency of her life to beat second seed Aryna Sabalenka within the semi-finals, saving a match level and combating again from 5-2 down within the deciding set.
However Swiatek had each the expertise and a formidable document in finals to bolster her confidence, whereas Muchova was via to this stage for the primary time.
She made a really nervous begin and it appeared Swiatek might come up towards little resistance however Muchova acquired on the board within the fourth sport and the remainder of the primary set was aggressive.
The Czech showcased the range she has in her sport towards Sabalenka, conserving the Australian Open champion off steadiness along with her courtroom craft and willingness to return to the web, and he or she produced some standout moments right here.
There have been simply too many unforced errors, although, whereas Swiatek was capable of maintain her favoured place in the midst of the baseline and dictate along with her heavy forehand.
A second break of serve gave Swiatek the opening set, making her the primary participant, male or feminine, to win their first seven units in Grand Slam finals.
When she moved 3-0 forward once more within the second, it appeared quantity eight was not far-off, however Muchova dug in and broke Swiatek for the primary time within the fifth sport with a superb operating forehand.
The vast majority of the group was prepared her to increase Swiatek additional and all of the sudden it was the Pole feeling the strain, with a double fault handing Muchova the possibility to serve for the set.
She couldn’t take it however one other shaky sport from Swiatek gave her a second likelihood and this time she made it over the road, clinching her third set level after a surprising all-court rally.
Muchova has struggled badly with accidents throughout her profession and it was solely final yr that docs informed her she may need to surrender the sport.
She rode her momentum initially of the decider by shifting right into a 2-0 lead as Swiatek threatened to implode however the 22-year-old pulled herself collectively shortly to degree.
They exchanged breaks once more within the seventh and eighth video games, with Muchova unable to tug away, and Swiatek regained the ascendancy when she fought off one other break level to carry for 5-4.
The strain of serving to remain within the contest proved an excessive amount of for Muchova, who made three errors earlier than double-faulting on match level in a merciless finish to an absorbing remaining.