Understand and learn the open stance in tennis: when it makes sense, how to hit it safely, with common mistakes, safety notes and FAQ.
In the open stance your feet are roughly parallel to the net at contact, instead of stepping the front foot toward the target. At clubs you see it often. It is not a fashion but the answer to time pressure: when the ball comes fast or you have to run far, there is no room for the step forward.
The honest answer to "is the open stance better?": not in general. In a study with 7 tennis teachers and 8 recreational players, racket speed at contact was slightly lower in the open stance (21.2 versus 22.3 m/s for the pros, 15.8 versus 16.4 m/s for the recreational players) [1], and arm loading was not higher in the open than in the square stance [1]. A second study with 13 advanced players found similar racket speed in both stances because shoulder and trunk compensated for the missing weight transfer [2]. And a newer study with 42 competitive players found a median of 6 km/h (running laterally) and 4 km/h (running diagonally inside) more ball speed in the square stance; accuracy did not differ clearly [3].
The health side: on a defensive, stretched ball the open stance is more demanding on the hip. In a lab study with 8 advanced players the defensive open stance showed higher forces and more extreme angles at the hip joint than the neutral or the offensive open stance [4]. The authors see a possible risk of overuse at the hip. These are lab values, not proven injuries.
How long does it take? You learn the basic stance in one or two sessions. Until you hit it cleanly under pace and pressure, expect weeks (practical experience, not a study).
The most important decision comes before the shot: do you have time for a step forward (neutral or semi-open stance) or must you hit open? On fast balls or balls arriving far away, open is often the only option. The LTA teaches adapting position to the incoming ball and hitting the ball in front of and beside the shoes [5].
Milestone: On 8 of 10 feeds you consciously choose between open and square before the bounce.
Load onto the back leg, knees bent, hips opened sideways to the net. The back leg is the engine. As on any forehand, pelvis rotation, trunk rotation and shoulder movement are the main contributors to racket speed [6].
Milestone: In the loading phase you feel pressure on the back leg, not on the heels.
Pelvis and trunk rotate toward the target, the arm follows. In a study of trunk muscles with 14 collegiate players, activity in the open and square stance did not differ significantly [7]. In short: the open stance needs no "harder" trunk work but a clean rotation.
Milestone: You hit 7 of 10 balls with rotation rather than only with the arm.
In contrast to the square stance you transfer less weight forward [2]. That means you need more balance. Stay on the balls of your feet and land stably after the shot.
Milestone: After 8 of 10 shots you stand stably without wobbling.
After the shot you go back to the centre with a side shuffle or crossover step and into the ready position. The LTA names it as a teaching point: return to the ready position after every shot [5].
Milestone: After 8 of 10 shots you are back in the centre before the opponent hits.
Make the open stance an emergency mode, not the standard: in training deliberately play 10 forehands in the square and 10 in the open stance in a row and compare which is more accurate. The study with 42 players found no clear accuracy difference [3] – for you it may be different. Your result decides when you hit open.
A stance where your feet are roughly parallel to the net at contact. It is often used when there is no time for a step forward.
Not in general. For arm and trunk, studies showed no higher load [1][7]. On defensive, stretched balls hip load was higher [4].
In a study with 42 competitive players ball speed was higher in the square stance [3]; for racket speed, other studies showed hardly any difference [2].
Choose by situation: time for a step – use it. No time – hit open and stay stable.
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