Kevin Nolan is a master of this tactic at Bolton they used it regularly. It was one of Sam Allardyce's favoured set-piece moves.
Here, Nolan deliberately sought out Steven Taylor's marker, Matthew Bates, to block him off and afford Taylor the space he required to thump home a header.
Look at the way Nolan faces away from the ball. Chelsea adopted thesame tactic under Jose Mourinho to free space for John Terry. When willEnglish referees act on this grappling? It was a pivotal goal, too.
The difficulty for the ref is that often this all happens before the ball comes into play and they are following the ball. You can warn a player or caution him, but you can't give a free-kick. The cute offenders know that.