Stretch four

In basketball, a stretch four (sometimes called combo forward or cornerman) 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.

While the term "combo forward" (or "cornerman") is now used interchangeably with "stretch four", the traditional use of the term "combo forward" was for a player who was frequently deployed in either of the forward positions in the team. Whilst most stretch fours could play the small forward position if necessary, many are solely used in the power forward position, or sometimes restricted to just the forward-center position (lacking the requisite small forward play element of a combo forward). Strictly speaking, not all stretch fours are combo forwards (and vice versa).

Some combo forwards are versatile enough to play three positions (the two forward positions and one additional position); examples include those skilled enough to also play the shooting guard position (i.e., they are both a swingman and a combo forward (cornerman), such as LeBron James, Paul Pierce, and Paul George). Meanwhile, other combo forwards have the requisite abilities to play both forward positions and the center position. These players are typically very tall (6'9" or greater) combo forwards like Kevin Garnett, Juwan Howard, and Clifford Robinson. Some of these players, such as LeBron James, also have very good play-making, ball-handling and passing abilities (especially in relation to their size), and hence can add a fourth position to their repertoire – that of the point guard (these forwards are known as point forwards).

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Wikipedia