Serena Williams’ former coach Rick Macci believes Alex Eala was “incorrectly” taught as a junior when working on her serve.

Eala is arguably the hottest property in tennis right now, as an army of fans follow her every move amid her ascent up the rankings.

After winning the Washington Open, in what was her first WTA Tour title, the 21-year-old has cracked the top 20 for the first time, but the youngster is not done yet.

However, many believe that if she wants to win a Grand Slam, she needs to improve her serve, which ranks outside of the top 50 for aces and first and second serve win percentage.

Rennae Stubbs initially said that the 21-year-old could not win a major but after her triumph in Washington, the Australian has softened that view. Moreover, Andy Roddick has outlined why the left-hander’s serve is trickier to deal with than meets the eye.

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But Macci, who has trained five No 1 ranked players in Roddick, Serena, Venus Williams, Maria Sharapova, and Jennifer Capriati, is not so complimentary.

The 71-year-old thinks it will be “almost impossible” to change Eala’s serve until the off season, her delivery needs big changes to improve it, and she doesn’t use her legs enough.

Roger Federer was praised for having such a smooth and technically sound serve but Macci thinks Eala is a long way from that.

He wrote on Instagram this week, “Almost impossible to change Eala’s serve ’till the off season. This is heavy-duty, in-depth reconstructive surgery, all science-based with a biomechanist.

“Any tip, suggestion, tweak or change is a band-aid. She is smooth, relaxed, and flowing but was taught incorrectly as a junior when growing [up].

“Number one culprit on the WTA Tour, the leg drive does not initiate racquet entry at the proper time. If you do millions of anything, it will get better, but the timing will never be like Federer.”

Earlier this week, Macci took to social media to say that if Eala can get “biomechanical help” on her serve, it is time to fasten your seatbelts with the Filipina.

While he is critical of her serve, the American tennis coach did laud her “lethal” groundstrokes, calling her the “Philippine Machine”. All eyes will be on Eala as she begins her Cincinnati Open campaign ahead of this year’s US Open.

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