Andy Murray teases more underarm aces after successful Indian Wells debut

WATCH: Murray visits the TC Desk after his second-round win over Carlos Alcaraz.

Firsts don't come that often for Andy Murray at this point in his career, but the 34-year-old three-time Grand Slam champion had never attempted serving underarm at a tour-level event—until now.

And he enjoyed immediate success. Murray hit an underarm ace at 1-1 in the first set against Carlos Alcaraz in their second-round BNP Paribas Open meeting, going on to win the highly competitive encounter 5-7, 6-3, 6-2.

"I've never done it on the tour before," he told press at Indian Wells. "The courts are so slow. Look, since Wimbledon, obviously made some improvements and was getting lots of free points, serving a lot of aces in the matches I played recently."

But against Alcaraz, Murray would finish with just three aces in three hours. So when he noticed the Spanish teenager retreating even further behind the baseline during the first set, he changed things up.

"He started returning from further back, so it was even harder to get free points. I thought if he's going to stand that far back and the court and the conditions, why not try it and see if I can bring him forward a little bit again. Wasn't expecting obviously to get an ace," Murray said.

"Yeah, he was so far back, he didn't obviously react."

Murray considered using the play again, but had built a big third-set lead and didn't want to interrupt his momentum.

But having now done it once, it's something he might try on other opponents.

"Yeah, certainly when guys are standing there to return serve now, it's a smart play," he said.

His next round will be against No.5 Alexander Zverev of Germany.

A former world No. 1, Murray is ranked No.121 on the ATP Tour.