Andy Murray made a winning return to action at the Brisbane International on Tuesday, while Nick Kyrgios fired 44 aces on his way to beating Ryan Harrison.
Murray missed most of last season with a hip problem and had spoken recently of still feeling some pain.
But the Scot impressed on his ATP Tour comeback, getting the better of Australian wildcard James Duckworth 6-3 6-4 in the first round to set up a clash with fourth seed Daniil Medvedev.
"I thought I did quite well," said Murray. "I think maybe both of us at the beginning of the match were a bit nervous, a few errors from the back of the court from both of us.
"But I think as the match went on, the rallies were a bit more entertaining. I think for the first match of the new year after quite a long break, it was alright."
Defending champion Kyrgios put on a big-serving display in a repeat of last year's final against Harrison, eventually winning 7-6 (7-5) 5-7 7-6 (7-5).
"I don't think [I can serve more aces in three sets]," said Kyrgios. "I needed every single one of them."
Kyrgios will meet Jeremy Chardy in the second round after the Frenchman came from behind to beat Jan-Lennard Struff, while Jo-Wilfried Tsonga set up a second-round clash with top seed Rafael Nadal by winning 7-6 (8-6) 6-4 against Thanasi Kokkinakis.
Denis Kudla, Alex de Minaur and Jordan Thompson were the other New Year's Day winners in Brisbane.