The WTA’s scramble to find a replacement host for the Chinese city of Shenzhen for its showpiece event led to the tournament finishing only hours before another flagship tournament kicked off at the Emirates Arena thousands of miles and several time zones away.
Having won the doubles final with Russian Veronika Kudermetova in Fort Worth on Monday evening, Mertens rushed to the airport and took three flights before touching down in Glasgow just before 10pm on Tuesday.
Belgium’s first tie against Slovakia began only 12 hours later, and Belgian captain Johan Van Herck felt unable to select Mertens – his best player – in singles, but she teamed up with Kirsten Flipkens in a 6-0 6-3 victory over Viktoria Kuzmova and Tereza Mihalikova.
Mertens, who is ranked 29th in singles and fifth in doubles, said: “When I played the finals (in Texas), I started at 5.30pm, and it was a little bit longer than expected because I had my flight at 10pm.
“I was still doing media and everything. It was 8.15pm, I was like, ‘Oh, my God, I’m not going to make it’. We rushed. I barely showered. We went to the airport. I was there like 8.55pm. They said, ‘We have four minutes for your bags’. One bag on the scale. ‘Two minutes. Oh, my God.’
“(With) my mum, we ran to the gate and we kind of made it. And then three flights, went to Madrid, went to London, and then to Glasgow. I slept like seven hours. A little nap in between. But it’s quite a journey.
“I’m feeling good. It was a long trip, but I’m dedicated to play for Belgium.”
Mertens was one of seven players due to compete in both events, although Jessica Pegula withdrew from the United States team on Monday and Barbora Krejcikova pulled out of the Czech side on Wednesday with a hand injury, dealing a major blow to their chances of winning another title.
World number one Iga Swiatek had already decided she could not play in both, leaving Poland with little chance of progressing.
The WTA and International Tennis Federation, which organises the Billie Jean King Cup, have promised to address the scheduling for future years.
Mertens said: “I’ll try to look at it in a positive way because I can’t change anything at this moment. Of course it could be very different.”
Belgium were beaten 2-1 by Slovakia but could still qualify with victory over Australia on Thursday.
Last year’s runners-up Switzerland claimed the first 3-0 victory of the competition over Italy, with Jil Teichmann winning a three-hour tussle against Elisabetta Cocciaretto before Belinda Bencic defeated Jasmine Paolini and Bencic and Teichmann teamed up to win the doubles.
The delay meant the tie between the USA and Poland was more than two hours late starting. The US rested their number one player, Coco Gauff, who contested singles and doubles at the WTA Finals.
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