HOUSTON, Oct. 5, 2012 /PRNewswire/ -- Sidewinder Drilling Inc. ("Sidewinder"), a Houston-based land drilling company controlled by Avista Capital Partners, today announced that its direct, wholly-owned subsidiary, Fastball Acquisition Inc. ("Fastball"), has commenced its cash tender offer for all outstanding shares of common stock of Union Drilling, Inc. ("Union Drilling") (NASDAQ: UDRL) at a price of $6.50 per share. The tender offer is being made in connection with the Agreement and Plan of Merger, dated as of September 24, 2012, among Sidewinder, Fastball and Union Drilling, which Sidewinder and Union Drilling announced on September 25, 2012. The Union Drilling board of directors has unanimously determined that, among other things, the tender offer is advisable, fair to and in the best interests of Union Drilling's stockholders and unanimously recommends that Union Drilling's stockholders accept the offer and tender their shares to Fastball. The tender offer and withdrawal rights are scheduled to expire at 12:00 Midnight ( New York time) at the end of the day on Friday, November 2, 2012, unless the tender offer is extended. Following the completion of the tender offer, Sidewinder will merge Fastball and Union Drilling, resulting in any shares not purchased in the tender offer being converted into the right to receive the same cash price per share as paid in the tender offer. The tender offer and the merger are subject to customary closing conditions set forth in the agreement and plan of merger, including the acquisition in the tender offer of at least 67.2% of Union Drilling's outstanding shares on a fully diluted basis and the expiration or early termination of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended. The closing of the acquisition is expected in the fourth quarter of 2012.