With a spot in the final four on the line, both singles players on the Singapore Indoor Stadium court last night were eager to be the next across the finish line.
The only issue: Neither could muster the momentum needed to claim the White Group's remaining berth decisively.
Despite it being a straight-sets win, world No. 5 Venus Williams had to labour for her 7-5, 6-4 result over Garbine Muguruza at the BNP Paribas WTA Finals Singapore presented by SC Global.
It is a win that allowed her to get her own back at the same opponent who defeated her in the Wimbledon final this year.
Williams joins Karolina Pliskova in the semi-finals. The Czech had already secured her place in the final four as group winner, even before she was beaten 6-3, 6-1 by Latvia's Jelena Ostapenko yesterday.
Neither of the big hitters on court last night were playing at their best, something world No. 2 Muguruza readily admitted later. The second set, in particular, was littered with seven breaks of serve.
But while her energy levels dropped visibly after taking the first set, Williams held her nerve and serve, before breaking her opponent when it mattered to take the match, her second win in the group.
Her 7-5, 6-7 (3-7), 7-5 win over Ostapenko on Tuesday involved the most number of games played in a three-set match in WTA Finals history. Williams, who was diagnosed in 2011 with the strength-sapping Sjogren's Syndrome, spent 3hr 13min winning that battle.
Having made a habit of giving terse answers at her post-match media conferences in Singapore, the one that took place last night was again a quick affair.
Asked if the win was sweet revenge for Wimbledon, the American said: "No, not at all. A win is a win, whether it's like today or yesterday... Yeah, pretty much, I'm just focused on Saturday, trying to win again."
Muguruza, meanwhile, could only give her opponent credit for stepping up when it counted. The Spaniard was 3-1 up in the second set yesterday but unable to force a rubber. She said: "I think (Williams) played very good in important moments, and I made few mistakes that I shouldn't.
"I wasn't trying to get frustrated because I knew I wasn't playing my best tennis. I was just trying to... be calm, not get crazy and kind of waiting for my opportunity. And it didn't come. In important moments, she stepped up and turned it around.
"I'm very proud of this year. It's not going to change. I knew here it's going to be tough... my year has been incredible... I improved so many things. That's what I'm going to take (with me)."
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