It is possible to manually fire two Ajax requests- one on the OnMouseOver and one for the OnClick event as shown in the mentioned help topic. However please note that in some circumstances this two events could fire one after another and this way two Ajax requests will fire at a time. In such case in order to avoid Ajax issue you could set RequestQueueSize property of the RadAjaxManager to a value grater than one.
Give this a try an verify if this helps.
the Telerik team
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