Taylor Fritz returns a shot to Ben Shelton at the BNP Paribas Open tennis tournament, March 11, 2023, in Indian Wells, California. (PHOTO / AP)

INDIAN WELLS, California - Defending champion Taylor Fritz battled back against fellow American young gun Ben Shelton 4-6 6-4 6-3 and top seed Carlos Alcaraz breezed past Thanasi Kokkinakis 6-3 6-3 in second-round action at Indian Wells on Saturday.

An energized Shelton came out firing, crushing an emphatic overhead to break Fritz's mighty serve en route to grabbing the first set and putting the tournament on upset watch.

The fourth-seeded Fritz held his nerve and converted the first break opportunity he saw on set point when Shelton dumped a forehand into the net to level the match at a set apiece

The fourth-seeded Fritz held his nerve and converted the first break opportunity he saw on set point when Shelton dumped a forehand into the net to level the match at a set apiece.

In the final game of the match Fritz showed that he is more than a big server, hitting a brilliant lob and deft drop shot to set up match point, which he converted when Shelton's attempt to block back a ferocious forehand sailed long.

"I expected him to come out serving bombs and playing well because he had nothing to lose," Fritz said of the 20-year-old Shelton.

"I had to regroup and problem-solve. He's an extremely tough first match to play, so I'm happy to get through it."

Ben Shelton returns to Taylor Fritz at the BNP Paribas Open tennis tournament, March 11, 2023, in Indian Wells, California. (PHOTO / AP)

Reigning US Open champion Alcaraz never faced a break point against Australia's Kokkinakis as the Spanish teenager cruised to a stress-free win in his first hard court match of the year.

Andy Murray enjoyed a rare straight-sets win over tournament lucky loser Radu Albot of Moldova 6-4 6-3 to set up an all-British third-round showdown with Jack Draper.

The veteran Murray said he expects a great match against the 21-year-old Draper, who he has mentored in the past and who beat Britain's Dan Evans 6-4 6-2 earlier in the day.

"I think he'll be a top player for a long time," Murray told reporters.

ALSO READ: Murray and Raducanu battle to victory at Indian Wells

In other men's results, Italian 11th seed Jannik Sinner beat Frenchman Richard Gasquet 6-3 7-6(2), eighth seed Felix Auger Aliassime of Canada was a 7-6(5) 6-4 winner over Spain's Pedro Martinez and Swiss Stan Wawrinka beat 26th seed Czech Miomir Kecmanovic 7-6(8) 6-4.

Swiatek crushes Liu

On the women's side, world number one and top seed Iga Swiatek got her title defense off to a dominant start with a 6-0 6-1 thrashing of Claire Liu.

"Tactically and tennis-wise, everything was on point, so I'm pretty happy with my game," said Swiatek,

The win sets up a blockbuster third-round match against 2019 Indian Wells and US Open champion Bianca Andreescu of Canada.

Emma Raducanu knocked out Polish 20th seed Magda Linette 7-6(3) 6-2 to notch her biggest win since triumphing at the US Open in 2021.

The 20-year-old Briton fell into a 4-1 first set hole but rallied from there, dictating points with her forehand to push Linette deep into the court.

She sealed the win by whipping a forehand winner down the line to bring the fans to their feet on a warm and windy day in the Southern California desert.

The win marked Raducanu's first back-to-back victories since September and is a hopeful sign that she may be moving beyond the multiple health issues that have beset her of late.

She suffered an ankle injury in the lead up to January's Australian Open, tonsillitis that forced her to withdraw ahead of last week's Austin Open and a flaring up of the wrist injury, which had cut short her 2022 season and required attention from a physiotherapist on Saturday.

"I'd say I feel more positive about my game today," Raducanu told reporters.

"The first day, I didn't really know what was going on. Today I felt pretty decent out there, especially with the conditions. It was really windy, and I did well to overcome it."

READ MORE: Raducanu reaches Indian Wells third round

She will next face Brazil's Beatriz Haddad Maia, who was a 5-7 7-6(4) 6-3 winner over Czech Katerina Siniakova.

The tournament's 2021 champion, Paula Badosa, scored a 6-2 7-5 win over fellow Spaniard Nuria Parrizas-Diaz in the night session.

Elsewhere, Czech Karolina Muchova scored an impressive 7-6(1) 6-3 win in her tournament debut over two-time champion Victoria Azarenka of Belarus and Czech Marketa Vondrousova crushed her compatriot, the 28th-seeded Marie Bouzkova, 6-1 6-1.