Full code after the jump.

View MXML

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2007/10/13/creating-donut-shaped-pie-charts-using-the-innerradius-style/ -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="middle"
        backgroundColor="white">

    <mx:Script>
        <![CDATA[
            private function labelFunc(item:Object, field:String, index:Number, percentValue:Number):String {
                return item.name + ": " + '\n' + "AVG: " + item.avg;
            }
        ]]>
    </mx:Script>

    <mx:ArrayCollection id="arrColl">
        <mx:source>
            <mx:Array>
                <mx:Object name="R Winn" obp=".353" slg=".445" avg=".300" />
                <mx:Object name="P Feliz" obp=".290" slg=".418" avg=".253" />
                <mx:Object name="O Vizquel" obp=".305" slg=".316" avg=".246" />
                <mx:Object name="B Molina" obp=".298" slg=".433" avg=".276" />
                <mx:Object name="R Durham" obp=".295" slg=".343" avg=".218" />
            </mx:Array>
        </mx:source>
    </mx:ArrayCollection>

    <mx:ApplicationControlBar dock="true">
        <mx:Label text="innerRadius:" />
        <mx:HSlider id="slider"
                minimum="0"
                maximum="0.5"
                liveDragging="true" />
    </mx:ApplicationControlBar>

    <mx:PieChart id="chart"
            height="100%"
            width="100%"
            innerRadius="{slider.value}"
            showDataTips="true"
            dataProvider="{arrColl}" >
        <mx:series>
            <mx:PieSeries labelPosition="callout"
                    field="avg"
                    labelFunction="labelFunc">
                <mx:calloutStroke>
                    <mx:Stroke weight="0"
                            color="0x888888"
                            alpha="100"/>
                </mx:calloutStroke>
                <mx:radialStroke>
                    <mx:Stroke weight="0"
                            color="#FFFFFF"
                            alpha="20"/>
                </mx:radialStroke>
                <mx:stroke>
                    <mx:Stroke color="0"
                            alpha="20"
                            weight="2"/>
                </mx:stroke>
            </mx:PieSeries>
        </mx:series>
    </mx:PieChart>

</mx:Application>

View source is enabled in the following example.