British number one Johanna Konta has confirmed that Michael Joyce will be her new coach.
BBC Sport reported in November that talks were ongoing to appoint the 44-year-old American.
Joyce reached a high of 64th in the world as a player, and spent six years as part of Maria Sharapova's team. He worked with Victoria Azarenka in 2017.
"Michael is a fantastic coach with a great pedigree," said Konta. "I feel like there is so much more to come."
Konta, who has not played since October because of a foot injury, climbed as high as fourth in the world in 2017.
Konta reached the semi-finals at Wimbledon and won the prestigious Miami Open this year while working with Belgian coach Wim Fissette. Their partnership ended soon after Konta narrowly failed to secure a place in the WTA Finals in Singapore following a run of five defeats.
Her first tournament with Joyce is set to be the Brisbane International, which starts on 31 December.
Sharapova won the US Open and the Australian Open and became world number one while being coached by Joyce.
By Russell Fuller, BBC tennis correspondent
Konta described Joyce as a fantastic coach with a great pedigree as she confirmed the American will travel with her full-time in 2018.
Joyce spent six years as part of Maria Sharapova's team and for much of this year has been working with Victoria Azarenka, who remains involved in a custody dispute.
Joyce will be Konta's third coach in as many years although change did her no harm last year when she replaced Esteban Carril with Wim Fissette and retained her place in the world's top 10.
The partnership's first test will come in Brisbane in the first week of January.
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