Cornerman (basketball)

In basketball, a stretch four (sometimes called combo forward or stretch big) is a player who plays in the power forward position. "Stretch" describes the effect such a player has on the opposition defense, and the power forward position is also known as the "four position"; hence "stretch four". The stretch four is a fairly recent innovation in the NBA (with an "explosion" of players coming through since the 1999-2000 season), but is still becoming increasingly common in today's game, as many NBA coaches now use the "small-ball" line-up/tactical play.

Power forwards (PF's) traditionally play close to the basket, using their size and strength to provide interior defense, posting-up (scoring close to the basket) and rebounding. A stretch four is a player that is of power forward size but has superior shooting skills (especially three-point jump shots). While using these skills on offense, the player retains the ability to defend the opposing power forward.

Stretch fours are tactically employed in this way to "stretch" the opponent's defense. The ability to score a high percentage of catch-and-shoot three-point shots from distance (the distinct feature of a stretch four) causes defensive problems for the opposing team, as it pulls the opposing (and crucially, defending) power forward out of the low post area, opening up driving lanes for guards to exploit (these can be running lanes or passing lanes). This also creates more post space and potentially scoring and rebounding opportunities for the center player.

Players with the same play style as stretch fours but play the center position are called stretch fives.

The combo forward position has become especially important in international play, where three-point shooting and floor spacing are more important due to the zone defenses used by many international teams, as well as the shorter three-point line (compared to the NBA). In recent years the U.S. men's senior basketball team has shown the importance of the international combo forward by playing players such as LeBron James and Carmelo Anthony as combo forward, to make use of their size and skills.

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Wikipedia