A new year is upon us, and that means it's time for you to make your voices heard once more: it's time to crown the first monthly award-winners of 2019! 

We narrowed down a list of worthy honorees to the four breakout players in January, but whose defining run impressed you the most? 

Have a look at the nominees in the video below and cast your vote for your favorite before voting ends Thursday at 11:59 p.m. ET!

Danielle Collins: Collins had a stunning fortnight Down Under, as the unseeded American knocked off three seeded players en route to her first Grand Slam semifinal.

The American was near-defeat in her first round match against No.14 seed Julia Goerges in the opening round, but rallied from a set and match points down to pull off a three-set stunner, and could hardly be stopped before Petra Kvitova ended her run in the final four.

Along the way, Collins also defeated No.19 seed Caroline Garcia and No.2 seed and three-time Grand Slam champion Angelique Kerber, the latter with just the loss of two games, and became the first former collegiate women’s player to reach a Grand Slam semifinal since Lori McNeil did it at Wimbledon in 1994.

Dayana Yastremska: The Ukrainian teenager had the best Grand Slam result of her young career in Australia, as she ousted home favorite Samantha Stosur and No.23 seed Carla Suárez Navarro en route to reaching the third round in just her second Grand Slam main draw before being stopped by 23-time Grand Slam champion Serena Williams. 

Read more: 'It's a dream come true' - From fan to foe, Yastremska readies for Serena showdown

In addition to her result in Melbourne, Yastremska reached the quarterfinals of the Hobart International and also ended January and began February with a run to her second WTA title at the Toyota Thailand Open in Hua Hin.

Amanda Anisimova: Anisimova made the biggest splash of all Down Under, as she knocked off two seeded players to reach the second week of a Grand Slam for the first time at the Australian Open. 

The 17-year-old upset Brisbane runner-up Lesia Tsurenko and Shenzhen champion Aryna Sabalenka for a spot in week two, where she was eventually cooled off by runner-up Kvitova.

Nonetheless, her run saw her become the first player born in the 2000s to reach the second week of a major, and the youngest American to do so since a then-16-year-old Serena Williams lost in the fourth round of rhe 1998 French Open.

Ashleigh Barty: Barty shined on home soil in January, as she made deep runs in each of the two events she played in Australia.

The home nation's No.1 reached the final of the Sydney International for the second straight year, which included a victory over then-World No.1 Simona Halep as well as notable scalps over Jelena Ostapenko, Elise Mertens and Kiki Bertens before she eventually fell to Kvitova in a titanic championship match.

Her good form continued through to Melbourne, where she reached her first career Grand Slam quarterfinal, and rallied from a set down to defeat Maria Sharapova to become the first Aussie woman to seal a spot in the last eight of her home major since Jelena Dokic in 2008.

The winner will be announced on Friday, February 8.

How it works: five hot shots are selected by wtatennis.com for every month, and the winner is then determined by a fan vote on wtatennis.com.