Karolina Pliskova delivered a statement of intent, beating Venus Williams 6-2 6-2 in the first match of the 2017 WTA Finals on Sunday.
Seven of the eight players are chasing the number one ranking in Singapore, with Pliskova looking much more likely than the veteran American on this evidence.
Williams, who beat Pliskova in the 2015 Elite Trophy final, could scale the rankings for the first time since June 2002 this week, but her chances took a dint in this White Group match as she struggled woefully on second serve and seemed caught between strategies when the ball was in play.
Pliskova's greater mobility routinely allowed her to steal points and the Czech showed a useful ability to accelerate into the back-end of sets to get her tournament off to a winning start.
The errors in Williams' game were evident early on as a double fault in her first service game presented Pliskova a break point, converted at the second time of asking thanks to a fizzing forehand up the line after dogged defence.
Williams was on the board in game four with her most potent service game and Pliskova meekly surrendered the advantage with a double fault, only to be outdone by the 37-year-old, whose radar was well off as she lost serve to love.
Pliskova rode out Williams' attempts to bring the contest under her spell and a positive approach on her opponents' second serve paid dividends as the seven-time grand slam champion chipped long to concede the first set.
Williams' approach in the second was notably odd, as she seemed to be holding back from her trademark power shots in an attempt to prolong rallies, which generally played into Pliskova's hands.
The tactic made for some marathon games, Pliskova holding the third after five deuces, but that only seemed to take steam out of Williams' next service game and a wild backhand miss put Pliskova on course for victory.
A firmly Williams-favouring crowd was briefly cheered by a spirited hold for 4-2, but it came between two love holds for Pliskova and a deserved victory was the Czech's when Williams went long again - the only former champion in the field with plenty to improve on if she is to challenge.
Ka Pliskova  bt V Williams  6-2 6-2
Pliskova - 25/12
Williams - 16/19
Pliskova - 5/2
Williams - 4/6
BREAK POINTS WON
Pliskova - 5/12
Williams - 1/3
FIRST SERVE PERCENTAGE
Pliskova - 63
Williams - 59
PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE
Pliskova - 78/53
Williams - 61/24
Pliskova - 68
Williams - 44