3 controversial calls, 2 weeks by 1 umpire: How Denis Shapovalov, Taylor Fritz & Felix Auger-Aliassime all ended up on the receiving end of Greg Allensworth's contentious decisions

American tennis umpire Greg Allensworth has been making headlines for all the wrong reasons in the last two weeks. The high-profile chair umpire has been involved in three controversial cases involving top tennis stars during the ongoing North American leg of the tennis season.

Allensworth has been in the thick of things while officiating at both the Mubadala Citi DC Open and the Cincinnati Masters. Allensworth was first involved in an incident with Denis Shapovalov in Washington and followed it up with incidents involving Taylor Fritz and Felix Auger-Aliassime in Cincinnati.

In the quarterfinals at the Mubadala Citi DC Open, Allensworth was the chair umpire for a match between Ben Shelton and Denis Shapovalov. Shelton won the first set 6-3 and the players were in the middle of a tie-break for the second set, when Shapovalov was disqualified for dissent.

After losing a point, Shapovalov threw his racquet on the ground and appeared to say something to a spectator. The chair umpire gave Shapovalov a code violation for unsportsmanlike conduct and called the supervisor to discuss the matter. The Canadian player insisted that the spectator abused him first and asked Allenworth not to call the supervisor. However, the supervisor was eventually called and Shapovalov was disqualified from the match.

Shelton was seen insisting with Allensworth that he heard the spectator talk to Shapovalov as well but the chair umpire stood his ground and decided to disqualify the Canadian. Later, Shapovalov appealed against his disqualification, which led to the ATP deciding he could retain his ranking points and prize money from the tournament.

Greg Allenworth in the headlines again for his controversial decisions at the Cincinnati Masters

After his controversial moment in Washington D.C., Allensworth was involved in similar incidents in Cincinnati, this time involving American star Taylor Fritz and Canadian Felix Auger-Aliassime. First, during the match between Fritz and Brandon Nakashima, Allensworth was involved in an argument with Fritz over a late call.

In the middle of the second set, Fritz returned a serve that looked to be more than a foot out but the call wasn't made by the umpire. Fritz glanced at Allensworth before continuing the play, before the American umpire stopped the play. Fritz immediately went to the chair umpire and started pleading his case but Allensworth did not change his mind and the point was replayed.

Though Fritz was adamant that the chair umpire should have called it out with the help of Electronic Line Calling, the point was ordered replayed. Fritz went on to win the replayed point and won the second set, but ended up losing the match in three sets.

Later, in the Round of 16, Allensworth was again in the thick of controversy during a match between Auger-Aliassime and Jack Draper. On match-point, Draper hit a winning half-volley which was adjudged to be legal by Allensworth but Auger-Aliassime claimed the ball bounced on Draper's side of the court before bouncing over the net.

Auger-Aliassime was left shocked by this decision and pleaded his case with the umpire. However, Allensworth stood by his decision that Draper had won the point and the match. The replays, crucially not available to the umpire, showed that Allensworth's call was incorrect and the point should have been awarded to Auger-Aliassime.

The Canadian tried his best to persuade the American umpire but his decision did not change. Auger-Aliassime called the decision "horrendous" before finally accepting his fate.

Greg Allensworth is one of the best tennis umpires on tour, but the last couple of weeks have been difficult for the American. Allensworth is one of only 33 Gold Badge Chair Umpires.