Brewing device for preparing beverages by mixing a pressurized flow with an edible substance provided inside of a capsule , whereby said brewing device presents from upstream to downstream: - a force transmission disposition adapted so that can convert a swivelling movement in a first direction around a rotation axis (I), into a piston-like linear movement along a displacement course between an upstream position where the brewing device is open, and a downstream position where the brewing device is closed, and vice-versa, - an injection disposition provided in connection with said force transmission disposition so that can be moved in a piston-like manner along the longitudinal direction of the brewing device , between an open position and a closed position thereof, and vice-versa, - a collection disposition arranged in stationary manner at a downstream position and adapted for retaining said capsule , presenting a collection chamber with upstream-oriented opening, and a discharge opening providing downstream fluid connection, - a structural disposition that provides support to said force transmission disposition , - whereby said injection disposition presents side supports adapted for supporting said capsule and provided sideways on both sides as grooves developing along a vertical direction and with inwards-oriented openings adapted to retain a part of said capsule , for example a collar-like radial projection, in a position generally aligned with the introduction onto said collection chamber , and - whereby said injection disposition further presents a support base provided on the downwards-oriented side of said injection disposition and extending beyond thereof, so as to provide support to a downwards-oriented part of said capsule , characterized in that said base support is provided so that can be moved together with said injection disposition , and be retained relative to said injection disposition , so that said base support only provides support to said capsule along an upstream part of the displacement course of said injection disposition . - a force transmission disposition adapted so that can convert a swivelling movement in a first direction around a rotation axis (I), into a piston-like linear movement along a displacement course between an upstream position where the brewing device is open, and a downstream position where the brewing device is closed, and vice-versa, - an injection disposition provided in connection with said force transmission disposition so that can be moved in a piston-like manner along the longitudinal direction of the brewing device , between an open position and a closed position thereof, and vice-versa, - a collection disposition arranged in stationary manner at a downstream position and adapted for retaining said capsule , presenting a collection chamber with upstream-oriented opening, and a discharge opening providing downstream fluid connection, - a structural disposition that provides support to said force transmission disposition , - whereby said injection disposition presents side supports adapted for supporting said capsule and provided sideways on both sides as grooves developing along a vertical direction and with inwards-oriented openings adapted to retain a part of said capsule , for example a collar-like radial projection, in a position generally aligned with the introduction onto said collection chamber , and - whereby said injection disposition further presents a support base provided on the downwards-oriented side of said injection disposition and extending beyond thereof, so as to provide support to a downwards-oriented part of said capsule , <EOS>