Professional foul stop the clock and get the ball back, rather than allow the opponent to run out the clock. In addition, there are specific rules governing obvious goal scoring opportunities called clear path fouls. The professional foul in rugby league embodies a similar concept to other sports, a deliberate breach of the rules in order to prevent a scoring opportunity. The penalty for this offence is 10 minutes in the sin bin. The majority of professional fouls are either holding down the tackled player after a break has been made in order to allow his teammates to reform in defence, interfering
First-move advantage in chess Bent Larsen wrote, annotating a game that began 1.c4 c5 2.b3 b6, "In symmetrical openings, White has a theoretical advantage, but in many of them it is only theoretical." GM Andrew Soltis wrote in 2008 that he hates playing against the symmetrical Petroff's Defense (1.e4 e5 2.Nf3 Nf6), and accordingly varies with 2.Nc3, the Vienna Game. However, there too he has been unable to find a way to an advantage after the symmetrical 2...Nc6 3.g3 g6 4.Bg2 Bg7, or after 3.Nf3 Nf6 ( to the Four Knights Game) 4.Bb5 Bb4 5.0-0 0-0 6.d3 d6 7.Bg5 Bg4 8.Nd5 Nd4 9.Nxb4 Nxb5,