Jack Draper's highly anticipated clash with Joao Fonseca was bizarrely interrupted in the first set. The Brazilian teenager was serving at 4-4 30-15 when a loud alarm went off on the court, leaving both players baffled.

Fonseca waved his arms in disbelief as the umpire raced to report the incident. Commentators were also stunned, questioning whether it was a technical error or a sign of an emergency.

Draper had a huge test in his opening match in Indian Wells. As the 13th seed, he received a bye into the second round to meet Fonseca - the teenage sensation who has taken the tennis world by storm and recently won his first tour title in Buenos Aires.

The stands were packed on Court 4, with plenty of Brazilians in attendance to cheer on their man. The British No. 1 got an early break but Fonseca immediately got back on serve and there was little separating them.

As the teenage wildcard stepped up to serve in an important game at 4-4 30-15, an alarm started blaring across the court, stopping Fonseca in his tracks.

"Okay… That is not your television, it’s also not the audio feed from Indian Wells, it is something actually on the grounds," Sky Sports commentator Jonathan Overend said.

"Incredibly loud by the looks of it, everyone sitting with their fingers in their ears," Naomi Broady replied.

Overend was concerned about the source of the noise, adding: "Hopefully it’s a malfunction of something to do with the audio system rather than an emergency alert."

Fonseca's fans used the brief interruption to spur him on, starting chants while the alarm continued to ring out. Chair umpire Tom Sweeney quickly alerted officials to the noise via his walkie-talkie, but the alarm stopped while he was speaking.

"We have a very, very loud alarm. It’s just stopped," he said as the crowd cheered when the noise finally ceased.

"Thank goodness. I don’t think anyone else could’ve listened to that for much longer. Could that slight interruption work in Jack Draper’s favour?" Overend asked as Fonseca lost the first point after the delay.

The disruption seemed to throw him off, the world No. 80 didn't win another point in the game and was swiftly broken. Draper had some trouble serving for the set, saving three break-back points, but he took it 6-4 after 46 minutes.

The 13th seed continued his demolition job, racing through set two to secure a 6-4 6-0 victory as Fonseca failed to win another game after the alarm incident.

The Brit was playing his first match since losing in the championship match of the Qatar Open last month. Following his run to the final in Doha, he pulled out of the ATP 500 in Dubai to rest.

Meanwhile, Fonseca was seeking his second consecutive victory over a British player after beating Jacob Fearnley in round one.