Justin Timberlake is being ordered onto the daddy track by wife Jessica Biel, who wants him to get her pregnant -- or else.

Photo: Getty Images

According to the National Enquirer, the lovebirds have been experiencing marriage woes because Jessica feels like her biological clock is ticking, and Justin just isn't listening. A source close to the couple says, "Jessica has been on him to start a family all year, and she finally snapped. That made Justin see sense because as scared as he is to be a dad, he’ll do anything to keep hold of Jessica. He knows she’s dead serious about this –- and he has no choice but to step up to the plate.”

The insider says that Justin is ready to buckle down and go for it -- in time for the couple's second wedding anniversary in October.

Dang!!! JT got his marching orders. Check out some pics of the Evolution of Justin Timberlake:

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