LUCKNOW, Dec. 17 -- Bilateral white-ball cricket series often end up with the focus less on the team outcome and more on individual storylines. Victory on Wednesday in the fourth T20 International against South Africa will give India an unassailable lead, but the real takeaway will be how the key players perform. Skipper Suryakumar Yadav's batting is declining so rapidly that another failure here could leave the team management and selectors worrying about the responsibility he will carry when defending the title in a World Cup that India co-host in barely two months. In 15 completed innings this year, his best is 24. The man with the 360-degree shot range has scored 12, 5 and 12 in this series. More concerning has been how he was caught in the first two games playing a touch too late. And in Dharamsala, with no pressure chasing 118 to win, his usually sure-fire flick that more often than not ends in the stands, was skied and caught at fine-leg after mistiming yet again. The 35-year-old has acknowledged that his lean spell with the bat is an issue. That brings the focus on Shubman Gill. There must be some relief in his run-a-ball 28 in Dharamsala, but with the buzz over how Sanju Samson has been kept out to help the vice-captain find momentum, Gill will be keen to produce a more authoritative knock. Will India rest Gill to give Samson a go, at least as part of the World Cup plans, needs to be explored. India though have a good record in Lucknow, having won all three T20Is played here. The mixed-soil pitch remains a spinner's paradise, characterised by its two-paced nature where the ball usually grips and turns, especially under lights with minimal dew. That could make chasing a target of around 190 tricky due to a slowing track. India have capitalised on these conditions in the past via spin and pace change-ups. But all-rounder Shivam Dube backed Surya and Gill. "He's (Surya) the kind of player who can make you win five out of five matches on his own. If he is not in form, it doesn't mean he's not a good player," he told the media on Tuesday. "Gill is such a player that even when his form is up or down, his average and strike rate are still very good. He has been performing for many years." Dube added: "It's cold here but Dharamsala was colder. We want to win and play good cricket. We want to improve. We always aim for a better show and we believe that all the players should try something new and improve so that we get to learn something from every match." Although Hardik Pandya is the main all-rounder as India build-up for the World Cup, India will look to the big-hitting and useful pace of Dubey too. "I worked a lot on my fitness in the off-season," he added. "I have a lot of conversations with Morne Morkel. That has helped me a lot."...