Men’s defending champion Jannik Sinner and women’s top seed Aryna Sabalenka both arrived at Wimbledon with question marks hanging over them but answered the doubters with contrasting first-round victories.Italy’s Sinner – playing his first match since his shock collapse and defeat in the second round of the French Open on a scorching day in Paris – was stretched to the limit by Serbia’s Miomir Kecmanovic but survived, winning 4-6, 6-3, 6-7(6), 6-2, 6-3 on Monday.Recommended Stories list of 4 itemsend of listSabalenka, who left Paris in a “deep, dark place” after losing the last 10 games of her quarterfinal against Diana Shnaider, followed Sinner onto Centre Court and breezed past Serbian qualifier Teodora Kostovic 6-2, 6-3.While world number one Sinner, the overwhelming favourite in the absence of Spain’s Carlos Alcaraz, lived to fight another day, there were some early seeded casualties.Norway’s 11th seed Casper Ruud was handed a tough draw in the shape of big-serving Pole Hubert Hurkacz and duly lost 6-4, 6-2, 7-6(7), while 12th seed Andrey Rublev was edged out in a five-set battle against fellow Russian Roman Safiullin, losing a deciding set tiebreaker 14-12 after missing two match points. Sabalenka celebrates beating Serbia’s Teodora Kostovic [Glyn Kirk/AFP]There was heartbreak too for surprise French Open runner-up Maja Chwalinska as she lost 2-6, 7-5, 6-2 to Thai qualifier Mananchaya Sawangkaew on Monday after the Pole fell and hurt herself while on match point.Several women’s seeds moved through on a day mercifully cooler than the heatwave that gripped London last week. Advertisement Japan’s Naomi Osaka once again dressed to impress, walking on court in a Kill Bill-inspired …