2003–04 campaign, the first Serie A season in the club's history, Siena finished in a respectable 13th place. In the 2004–05 Serie A campaign, with Luigi De Canio as head coach, Siena struggled for long periods of the season, languishing in the relegation zone for a great part of the campaign, and with the team drawing far too many games and barely recording any wins, they looked almost certain to be relegated. However, a resurgence of form towards of the end of the season gave them hope, and a 2–1 win against already relegated Atalanta on the last day saw them secure safety and an acceptable 14th place in the table. The 2005–06 season also saw Siena fighting hard and it successfully kept its place in Serie A. They ended the season in 17th place. For the 2006–07 season, Mario Beretta, who led Parma during the previous season, was appointed as new head coach. He kept Siena in Serie A after a 2–1 home win against Lazio in the final matchday. During the 2006–07 season, club chairman Paolo De Luca, who took over in 2001 and helped the club to their first historical Serie A promotion, started talks to sell the club to a conglomerate of Tuscan businessmen led by Giovanni Lombardi Stronati, chairman of Valle del Giovenco. The bid was finalised on 30 March 2007, one day before De Luca died after a long illness. The head coach for the 2007–08 campaign was expected to be Andrea Mandorlini, but he left the club by mutual consent on 12 November. Former coach Mario Beretta once again took charge. The club also explored the possibility of changing its denomination to include the name of their main sponsor, Banca Monte dei Paschi di Siena. On 9 July 2007, the club announced it had changed their denomination to "A.C. Siena Montepaschi". However, the name change needed to be accepted by the Italian Football Federation (FIGC) to become official: After the refusal by FIGC, this idea was abandoned. The club was then acquired by Massimo Mezzaroma, with Valentina Mezzaroma as vice-chairman. On 7 May 2011, Siena were once again promoted to Serie A after finishing second in the 2010–11 Serie B. The club's stint into the top flight lasted two seasons, as they were relegated after ending the 2012–13 Serie A in 19th place. Siena failed to register for 2014–15 Serie B on 15