Andreescu and Barty barged into the top of the women's game during the 2019 season. (AP)

With the completion of the year-end championships, the 2019 WTA season is officially in the books. It was a year that saw four different Grand Slam champions, two new names in the Top 5 and established players being tested in ways no one could have expected. 

It was a season that was impossible to see coming, and also one that many are glad they experienced. 

Here are the top five WTA surprises of 2019: 

1

#BibiRisen

A year ago, Bianca Andreescu was ranked No. 178 in the world.

She then won the ITF tournament in Norman, Okla., won seven straight matches to make the Auckland final, won the 125K in Newport Beach, Calif. and plowed through the Indian Wells draw to win the BNP Paribas Open. She then missed much of the middle of the season with a shoulder injury, won the Premier 5 Rogers Cup in her hometown of Toronto and defeated four seeds, including Serena Williams in the final, to win the US Open. 

Andreescu finishes the season with a 48-7 record, and a rankings jump of 173 spots, to No. 5, having made the most meteoric rise of a player in recent memory. 

 
 
 
 
 
 
 
 
 
 
 
 
 

SHOOK

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2

Barty's Dominance 

Ashleigh Barty, the year-end No. 1, is a new face in the Top 5 as well, having entered the season at a career-high ranking of No. 15. Barty took her career to a completely new level in 2019, with titles at the Miami Open, Roland Garros, the Nature Valley Classic and the WTA Finals, reshaping the landscape of the tour, and doing a whole lot of winning along the way:  

3

 Halep's "Match of Her Life"

Simona Halep had been expected for years to win a Slam at the French Open, or maybe even one of the hard-court majors. But no one was holding their breath for her to win Wimbledon—that is, until she actually did it, defeating Serena Williams, 6-2, 6-2, in 56 minutes. While lots of players' seasons were defined over the course 10-plus months, Halep's was changed in the span of an hour. And the impact on her resume was no less grand. 

4

Osaka's End-of-Season Recovery

Naomi Osaka's season was surprising in three different directions. First, when no one was sure what she'd make of the pressure of being a new star, she turned around a three-set final at the Australian Open, to win her second Slam. She then went title-less and final-less for the bulk of the season, failing to follow up on last year's wins in Indian Wells and at the US Open.

However, in maybe the biggest change-up of all, Osaka returned to prominence at the end of the season, with an 11-match winning streak that included titles at the Premier-level Pan Pacific Open and Premier Mandatory China Open, in which she beat both Barty and Andreescu, leaving little room to doubt her potential going forward. 

 
 
 
 
 
 
 
 
 
 
 
 
 

Xièxiè Beijing ❤️ #5

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5

Bencic's Top-10 Return 

Belinda Bencic started the season ranked No. 54, but quickly proved to be one of the most dangerous dangerous players on tour—just ask Osaka, who had both her Indian Wells and US Open defenses stopped by the Swiss. With titles at the Premier 5 in Dubai and the Premier-level Kremlin Cup, Bencic made it back to the Top 8 for the first time since 2016, carving out the spot that's felt for a while as if it should have been hers. 

 
 
 
 
 
 
 
 
 
 
 
 
 

No words needed✨ Dubai 2019! What a week???? @ddftennis

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