Elise Mertens had less than 24 hours between competing in Texas at the WTA Finals and reaching Glasgow for her Billie Jean King Cup Finals (BJKC) match.On Monday night, Mertens hurried to the airport after winning the doubles match with Veronika Kudermetova in Fort Worth. She boarded three flights before landing in Glasgow for the BJKC. Only 12 hours later, Belgium's opening match against Slovakia got underway.Though Johan Van Herck was unwilling to pick Mertens for the BJKC match, she partnered up with Kirsten Flipkens and defeated Viktoria Kuzmova and Tereza Mihalikova by a score of 6-0, 6-3.Billie Jean King Cup@BJKCupA whirlwind 38 hours and 43 minutes, ey, @elise_mertens? Time for some #BJKCupFinals12912A whirlwind 38 hours and 43 minutes, ey, @elise_mertens? 😅Time for some 😴#BJKCupFinals https://t.co/xQyTm8EzCaMertens was one of seven athletes scheduled to compete in both competitions this year. The chances of capturing a second BJKC title for the Czech Republic were severely hampered when Barbora Krejcikova decided to withdraw from the squad on Wednesday due to a hand injury. Jessica Pegula also withdrew from the United States team on Monday.Tennis fans on Twitter jumped in to talk about the scheduling conflict between the two competitions. One fan stated that it harms the player's health, writing:"Are you proud of being ridiculous? This schedule was stupid and harmful from the start. Anyone responsible would be fired in a serious company."Bartosz S@BSlawinsk@BJKCup @elise_mertens Are you proud of being ridiculous? This schedule was stupid and harmful from the start. Anyone responsible would be fired in a serious company.20@BJKCup @elise_mertens Are you proud of being ridiculous? This schedule was stupid and harmful from the start. Anyone responsible would be fired in a serious company.Another user claimed that while he was happy for Mertens, this situation is nothing to be proud of for either the WTA or ITF. He added that this was why Iga Swiatek decided against competing in the Billie Jean King Cup this year."I'm happy for Elise but yikes this is nothing to be proud of for either the WTA or ITF. This is like a decent part of the reason Iga isn't playing the BJK Cup," one tweet read.Lachlan Hall@lhall98@BJKCup @elise_mertens I'm happy for Elise but yikes this is nothing to be proud of for either the WTA or ITF. This is like a decent part of the reason Iga isn't playing the BJK Cup3@BJKCup @elise_mertens I'm happy for Elise but yikes this is nothing to be proud of for either the WTA or ITF. This is like a decent part of the reason Iga isn't playing the BJK CupHere are a few more reactions from fans:CRoq@CRoq14164484@BJKCup @elise_mertens For me, I'd rather have ordinary days/weeks of my life while waiting for my favorite players to have their well deserved vacation/rest or monitored training behind the scenes rather than me dying to see them recover from injury for months. Even a machine needs some cooling down.1@BJKCup @elise_mertens For me, I'd rather have ordinary days/weeks of my life while waiting for my favorite players to have their well deserved vacation/rest or monitored training behind the scenes rather than me dying to see them recover from injury for months. Even a machine needs some cooling down.Asia@creative_name00@BJKCup @elise_mertens risking players health .. you can be proud of yourself 351@BJKCup @elise_mertens risking players health .. you can be proud of yourself 💀heszke_meszke@MeszkeHeszke@BJKCup @elise_mertens Do you boast about it? you should be ashamed that you couldn't get along with the conditions so that all players could play comfortably.4@BJKCup @elise_mertens Do you boast about it? you should be ashamed that you couldn't get along with the conditions so that all players could play comfortably.Roksanche@Roksanche@BJKCup @elise_mertens You guys have no shame241@BJKCup @elise_mertens You guys have no shameOliwia@Olywia90626741@BJKCup @elise_mertens There is nothing to be proud of...4@BJKCup @elise_mertens There is nothing to be proud of...Jim O'Leary@jim_oleary@BJKCup @elise_mertens this isn't the flex you think it is@BJKCup @elise_mertens this isn't the flex you think it isG | mourning legends era 🏳️‍🌈@gigaswiatek@BJKCup @elise_mertens I was coming to shame y’all about promoting this but I realized everyone else is already doing that LMFAO@BJKCup @elise_mertens I was coming to shame y’all about promoting this but I realized everyone else is already doing that LMFAOMagda@_Magdus_@BJKCup @elise_mertens I hope you won’t get injured Elise and I hope you get plenty of rest. I hope that WTA/ITF hire people who can plan major events/tournaments better. It’s not that hard to figure it out. Don’t schedule them less than a week between, simple math really.@BJKCup @elise_mertens I hope you won’t get injured Elise and I hope you get plenty of rest. I hope that WTA/ITF hire people who can plan major events/tournaments better. It’s not that hard to figure it out. Don’t schedule them less than a week between, simple math really.Lukas@perounos@BJKCup @elise_mertens Low from @BJKCup , all fighting for women equal prize and treatment and now celebrating exploitation of players? Disappointing from both mental and physical health @BillieJeanKing@BJKCup @elise_mertens Low from @BJKCup , all fighting for women equal prize and treatment and now celebrating exploitation of players? Disappointing from both mental and physical health @BillieJeanKingJI@juanignacio_acFor the surprise of absolutely nobody, this ended in the worst possible way. Mertens had to retire mid 3rd set twitter.com/BJKCup/status/…Billie Jean King Cup@BJKCupA whirlwind 38 hours and 43 minutes, ey, @elise_mertens? Time for some #BJKCupFinals416A whirlwind 38 hours and 43 minutes, ey, @elise_mertens? 😅Time for some 😴#BJKCupFinals https://t.co/xQyTm8EzCaFor the surprise of absolutely nobody, this ended in the worst possible way. Mertens had to retire mid 3rd set twitter.com/BJKCup/status/… https://t.co/PbqjXzXRKGGreat Britain's semifinal chances at Billie Jean King Cup Finals remain alive following Spain's defeat of KazakhstanGreat Britain can still qualify for the semifinals of the Billie Jean King Cup.Spain's victory against Kazakhstan in Glasgow left Group C in doubt, reviving Great Britain's chances of making it to the semifinals of the Billie Jean King Cup Finals.Kazakhstan defeated Great Britain 2-1 in their opening game and with a win over Spain, they would have taken first place. But Nuria Parrizas Diaz and Paula Badosa's wins in the singles match were the ones that broke the tie.With a victory over Great Britain on Thursday, Spain will qualify. Spain earlier beat Kazakhstan in the doubles match, meaning Great Britain needs to defeat Spain 3-0 to keep their hopes alive.Moreover, Danielle Collins gave the United States a winning start by defeating Magdalena Frech of Poland 6-3, 3-6, 7-6(2). Following her rapid turnaround from the WTA Finals in Texas, Coco Gauff was left out of the USA singles team on the first day.