San Francisco Frontiers - 'Suffering' Djokovic fights past Cilic in Shanghai opener

The 38-year-old Serb is aiming for a record-extending fifth title in Shanghai, where he was greeted by rapturous cheers as he entered a stadium packed with adoring Chinese fans.

The combined age of Djokovic and Cilic -- 75 years and 139 days -- was the oldest ever between two opponents in an ATP Masters 1000 main draw match.

"I did enjoy it, but I also suffered a lot on the court," said Djokovic.

"It was a very close match. He was probably the better player for the first set," he added, saying he needed to "fire up all engines".

The first set was hard-fought, with 94th-ranked Cilic's best chance to break the 24-time Grand Slam champion coming but going in the 11th game.

Djokovic seemed to regain his footing in the tiebreak, steaming ahead to prevail 7-2.

In the second set the world number five broke the Croat in the third game and then kept his cool in a tense 10th game to secure victory with a final ace.

Last year Djokovic lost to world number two Jannik Sinner in the final.

On Thursday he said he would "love to have the chance" to play Sinner again if they meet in the semi-finals.

Sinner will start his campaign against Germany's Daniel Altmaier on Saturday.

- Shelton out -

The United States' Ben Shelton became the first top-10 seed to be booted out of the competition, beaten by 83rd-ranked David Goffin in straight sets.

The Belgian underdog beat 22-year-old Shelton, ranked sixth in the world, 6-2, 6-4.

Starting strong, the 34-year-old broke the American's serve in the third and seventh games to take the first set in just over half an hour.

The second was more closely fought, but shortly after play resumed following a rain break, Goffin broke in the ninth game after an unforced error by Shelton.

"It was tough to finish it, but I made it with a good service game, so I'm really happy," said Goffin.

Shelton has been recovering from a shoulder injury sustained at the US Open.

However, Goffin has form when it comes to eliminating top players.

In March this year he upset world number one Carlos Alcaraz in Miami and last year in Shanghai he knocked out world number three Alexander Zverev.

Teenager Learner Tien -- fresh from losing the final of the China Open against Sinner in Beijing on Wednesday -- continued his recent good form, beating Serbia's Miomir Kecmanovic to advance into the second round.

Top-ranked Alcaraz is not in Shanghai after pulling out to rest having won the Japan Open.

P.Adams--SFF