The blue and papaya orange MCL34 car was unveiled by 34 team employees at the former champions' Woking headquarters before Sainz and 19-year-old British rookie team mate Lando Norris stepped up to admire it.
Austin is a favourite track for the 34-year-old Mercedes driver and he will also be fancied to round up his Texan win tally to six on Sunday.
Champions Mercedes are chasing a sixth successive double, and Lewis Hamilton his sixth drivers' title, but the task looks tougher than ever.
'The phenomenal Max Verstappen was both sloppy and superb in Germany, getting caught out during the first two starts, and even spinning his car around to give the crowd something to gasp at with a Batmobile-esque 360 degree turn. 'After Hamilton crashed and Verstappen sniffed victory, though, he pounced hard, put his foot down, and took a deserved race win,' says Rediff's F1 columnist Raja Sen.
Lewis Hamilton led every lap from pole position to chequered flag, banging in a fastest lap for good measure to emphasise his supremacy
Lewis Hamilton won the Mexican Grand Prix for Mercedes after a first-lap scare on Sunday but the Briton will have to wait another week to wrap up his sixth Formula One world championship. Hamilton's 10th win of the season, and 83rd of his career, was also a 100th for Mercedes as a constructor.
Lewis Hamilton won the Chinese Grand Prix to seize the overall lead from his Mercedes team mate Valtteri Bottas in Formula One's 1,000th world championship race on Sunday.
'The most important thing, I think, is really about finishing races and analysing and making sure you get as many race points as you can, of course'
Russian fertiliser group Uralkali said that by turning down its higher bid for the company, the administrators had denied the extra funds that would have accrued to the shareholder of Force India - Mallya's Orange India Holdings Sarl - which is subject to a freezing order issued by the UK's High Court in favour of his 13 creditor Indian banks, led by the State Bank of India.
Red Bull's Max Verstappen celebrated his first Formula One pole position at the Hungarian Grand Prix on Saturday.
In a race of safety cars and surprises, Verstappen's former team mate Pierre Gasly made a first podium appearance in second place for Red Bull-owned Toro Rosso, a rare Honda-powered one-two.
Formula One leader Lewis Hamilton put Mercedes on pole position for their 200th race at the German Grand Prix on Saturday while engine problems dashed Ferrari's hopes.
The Finn lapped the six-km Baku street circuit in one minute, 40.495 seconds, just 0.059 seconds faster than team mate and championship leader Lewis Hamilton.
The Formula One season starts in Australia on March 17 with new regulations, changed lineups, a trio of young rookies fresh from Formula Two and the comeback of Poland's Robert Kubica.
Michael Schumacher's son Mick has followed in his father's footsteps by signing a contract with Ferrari to join the Formula One team's young driver academy. The 19-year-old German, whose father won five of his record seven championships with the Italian team, will be competing in Formula Two this year after winning the European F3 title in 2018.
Monaco's Leclerc, who had started on pole position for the first time, lost power with 10 laps to go while leading and finished third with an extra point for the fastest lap.
Summary of sports events and persons who made news on Monday
Summary of sports events and persons who made news on Wednesday
Sahara Force India's six-race point streak ended at the German Grand Prix as Paul di Resta and Adrian Sutil finished 11th and 13th respectively, at the Nurburgring circuit on Sunday.
Summary of sports events and persons who made news on Friday
The Indo-Belarusian pair easily beat Lucas Arnold and Mariano Hood of Argentina in the final.\n\n
India became the first team to qualify for the semi-finals of the ICC World Twenty20 after a thumping eight-wicket victory over Bangladesh in a Group 2 match, in Mirpur, on Friday. After restricting the hosts to 138 for 7, courtesy yet another dominating performance by the spinners, their batsmen hit up the required runs easily, with nine balls to spare.
Soccer's governing body FIFA has agreed to ban the third-party ownership (TPO) of players, its president Sepp Blatter said on Friday, seven years after first promising to outlaw the practice.