Andretti Autosport has found its fifth and likely final entry for the Indianapolis 500 with the addition of Simona de Silvestro to the lineup.

The Swiss-born de Silvestro ran last weekend's season-opening race at St. Petersburg for Andretti and finished 18th. Team owner Michael Andretti said he was hoping to add her for the Indy 500, and on Thursday announced she'll drive the No. 29 TE Connectivity Honda.

Andretti won the race last year with Ryan Hunter-Reay, and will field cars this season for Hunter-Reay, Marco Andretti, Carlos Munoz, Justin Wilson and de Silvestro.

De Silvestro left IndyCar last season to become a test driver in Formula One, but her funding package fell apart and she's trying to put together a return to full-time IndyCar racing.