Federer's SABR revival backfires spectacularly

Roger Federer's attempted revival of his revolutionary SABR tactic backfired spectacularly against Jan-Lennard Struff at the Australian Open on Thursday night.

The Swiss great introduced the move -- Sneak Attack By Roger -- in 2015 and its rare use continues to shock fans and commentators alike.

Not to mention opponents.

Federer was down 0-40 in the ninth game of the second set on Rod Laver Arena when he decided to bring it out.

SABR involves the receiver shuffling quickly towards the service line while the server is in his motion, enabling a half-volley return to put the pressure on.

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But any move that relies on the opponent is fraught with danger -- and the resurrection didn't quite go to plan for Federer.

Struff's serve caught the net cord, and right as Federer's snappy forehand sent the ball back over the net the chair umpire called let.

The reigning champion appeared disappointed at first as he returned to his mark for the repeat first serve, but his opponent was counting his lucky stars.

"Struff is looking right at us and smiling and laughing at that," Jim Courier said in commentary.

"That was pretty sweet."

Struff went on to win the point and the game when Federer returned wide with a backhand, though the world No.2 served out the set just minutes later.

Federer was challenged by Struff in the third set but went on to win the match 6-4 6-4 7-6 (7-4) and progress to a third-round match against French 29th seed Richard Gasquet tomorrow.

With Saturday set to be much cooler than the 40-degree temperatures seen on Thursday and Friday, Federer will again avoid playing in the hottest hours of the day.