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 better for White, while 1.b3 is playable but less likely to yield an opening advantage than 1.e4 or 1.d4. Watson concludes that Rowson writes that "in general one would assume that whatever advantage White has would be revealed most clearly in symmetrical positions." Accordingly, Watson, Suba, Evans, and the eminent player and theorist Aron Nimzowitsch (1886–1935) have all argued that it is in Black's interest to avoid symmetry. Nonetheless, even symmetrical opening lines sometimes illustrate the tenuous nature of White's advantage, in several respects. It is often difficult for White to prove an advantage in symmetrical opening lines. As GM