Tackle (football move) boots. Referees are encouraged to at the very least caution (yellow card) players who commit such challenges. Additionally, an illegal tackle which is also a professional foul is considered misconduct. The most spectacular form of tackle in association football is the slide tackle, wherein a tackler slides, leg extended, along the ground, aiming to hit the ball away. This form of tackle carries a high risk of committing a foul. "Diving" is association football involves tackled players exaggerating the physicality of tackles, so as to gain favourable decisions from the referee. In Australian rules football, the move commonly described as
First-move advantage in chess games beginning 1.d4 (moving the queen's pawn 2 spaces forwards). The main reason that 1.e4 was less effective than 1.d4 was the Sicilian Defence (1.e4 c5), which gave White only a 52.3% score in 145,996 games. Statistician Jeff Sonas, in examining data from 266,000 games played between 1994 and 2001, concluded that White scored 54.1767% plus 0.001164 times White's Elo rating advantage, treating White's rating advantage as +390 if it is better than +390, or −460 if it is worse than −460. He found that White's advantage is equivalent to 35 rating points, i.e. if White has a rating 35