How to check an InputRadio radio button in Blazor by default

Using Blazor Server, I am trying to setup some radio buttons within a form and check the first one by default.

I'm using InputRadio within an EditForm and setting checked="checked" or checked="true" but it's not working, the button is unchecked.

Sample code below. TestModel is a class with a single int property called Number.

@page "/Test"<div><EditForm Model="@_model"><InputRadioGroup @bind-Value="_model.Number"> <div><InputRadio id="1radio" Value="1" checked="checked" /><label for="1radio">1</label></div><div><InputRadio id="2radio" Value="2" /><label for="2radio">2</label></div></InputRadioGroup></EditForm> </div>@code {    private TestModel _model = new();}