Purpose:
Small-sided games (SS G) with floaters are frequently adopted during the training process of soccer players. However, no study has previously investigated how the rules imposed to these additional players impact the physical, tactical, and physiological responses of the regular players. This study aimed to analyse the influence of the number of floaters on players’ tactical behaviour, physical demands, and physiological responses in soccer SS Gs and to compare these variables between players with different positional statuses.

Methods:
Overall, 32 U-13 (n = 16) and U-14 (n = 16) players participated in this study, performing four 4-minute 3 vs. 3 SS Gs in both 1-floater and 2-floater formats. The frequency of core tactical principles, time-motion variables, and heart rate were used to describe the game multifactorial phenomenon.

Results:
Results showed an increased number of tactical actions of delays, defensive coverage, and width and length without ball actions in the 2-floater SS G without differences in physical demands or physiological response. Midfielders presented higher frequencies of penetration and offensive coverage, and lower frequencies of actions of width and length without the ball. There were also higher physical and physiological responses in midfielders.

Conclusions:
In conclusion, the 2-floater 3 vs. 3 format may be an important pedagogical strategy to promote a higher ball circulation pattern during SS Gs. Midfielders are the most demanded players tactically, physically, and physiologically in 3 vs. 3 SS Gs with floaters.