It was my real pleasure to have had the chance to work with Sloane in 2010-11 and updating her service was maybe the most enjoyable instant success of my coaching career in tennis. During our first meeting on the court in Florida in 2010, Sloane, as this is quite usual with most of the young players until today, didn't have a clear understanding about the (targeted) pronation. Following short verbal, visual and proprioceptive explanation of this motion and its key elements (including the Service 3.0 Code) from my side, Sloane wanted
The very well developed essential elements of a good service are here mainly a well-controlled toss, excellent eye control of the ball, a good build-up of a tension in the body and a sound understanding of the targeted pronation channeling energy against the target in the first part of the follow through. Such a solid Service 3.0 is an excellent base for further growth and shows that good developmental technical work on service was done with Kayla in the past.
Already in the late 90's, Mirjana belonged to the most dominant serving female players on the WTA Tour as she was one of the first of them who really understood the efficient use of the pronation. On the photos from 1998 shown below is well visible how fast she was able to pronate with the integration of the body energy already in the age of 16 years