Chipotle Mexican Grill  (CMG) - Get Report has extended free delivery service through the end of April as it scrambles to keep sales flowing and as analysts grow increasingly concerned about the impact of the coronavirus economic shutdown on the fast-casual Mexican brand and other restaurants.

Chipotle's move to extend the free delivery offer, first rolled out in March, comes as analysts at SunTrust Robinson Humphrey slashed their price target on shares of the chain more than 20% to $841 a share, down from $1,010 previously.

Still, the new price target allows for significant growth potential, with Chipotle shares trading at $624 a share after a sharp, 4.65% drop Wednesday amid the larger market selloff.

Even so, SunTrust analyst Jake Bartlett reaffirmed his buy rating on Chipotle, calling the chain "relatively well-positioned among fast-casual concepts" to weather the economic fallout from the deadly virus, which has prompted states across the country to shutter dine-in restaurant service.

Chipotle already had strong takeout numbers and digital service numbers before the crisis, with online sales amounting to roughly 20% of revenue, Bartlett wrote.

The SunTrust analyst expects Chipotle's same-store sales to plunge 40% before bottoming out, expecting the fast-casual Mexican chain will then "recover faster than its peers."

And Chipotle's balance sheet is a "fortress," with no debt and $881 million in cash and other investments to help the restaurant chain ride out the crisis, Bartlett wrote.

Morgan Stanley, KeyBanc and Bernstein also  recently lowered their price targets on Chipotle, with Morgan Stanley making the deepest cut, down to $602 a share, or more than $22 below what the restaurant chain is current trading at.