U.S. Pro Indoor

The U.S. Professional Indoor Championships, also known as U.S. Pro Indoor, was a professional tennis tournament founded in 1962 as the Philadelphia Invitational Indoor Tennis Championships. The tournament was held in Philadelphia, United States from 1962 to 1998. It played on indoor carpet courts, and indoor hard courts. It was an ILTF sanctioned event from 1962 to 1967 and again in 1970, the World Championship Tennis (WCT) circuit in 1968, 1969 and from 1971 to 1977 and the Grand Prix Tour from 1978 to 1989 before being held on the ATP Tour. It was held annually first at the Spectrum, and then at the CoreStates Center. It was originally named the Philadelphia Indoor Open Tournament prior to the open era.

History
The tournament was founded in 1962 as the Philadelphia Invitational Indoor Tennis Championships. This tournament until 1970 was part of the ILTF World Circuit. In 1964 the tournament was also known as the Philadelphia Indoor Championships. In 1969 the name was changed to the Philadelphia International Indoor Open Championships. In 1970 the tournament was organised by the International Tennis Players Association (founded in 1965 as the International Professional Tennis Players Association) and branded as the International Tennis Players Association Open Indoor or ITPA Open Indoor. In 1971 the tournament was re-branded as the Philadelphia International Indoor Open Championships also called the Philadelphia International Indoor

In 1972 the United States Professional Indoor tennis championships were created in Philadelphia, United States, as part of the WCT circuit, rival of the National Tennis League (NTL). As the first event of the season, the Philadelphia U.S. Professional Indoor attracted all WCT stars at the Philadelphia Spectrum at each of its yearly editions, with Rod Laver, John Newcombe or Marty Riessen winning the event in the early 1970s. After the WCT absorbed the NTL in 1970, the tournament continued to exist within the WCT tour until 1978, when the event officially became part of the Grand Prix Tour, precursor of the current ATP Tour.

As part of the Grand Prix's top tier tournaments until 1986, the Philadelphia event known as the U.S. Pro Indoor since 1973, saw American players dominating the fields in the 1970s and 1980s, with Tim Mayotte reaching four finals, World No. 1s Jimmy Connors and John McEnroe six finals each, and Czechoslovak Ivan Lendl three. In 1985, Swiss watch company Ebel S.A. started its six-year sponsorship of the event, the tournament becoming until 1990 the Ebel U.S. Pro Indoor. The event entered the new ATP circuit in 1990 as part of the Championship Series, to see eighteen-year-old, and future US Open champion Pete Sampras win his first career title against Andrés Gómez.

In 1991, the event lost Ebel's sponsorship, and went back to being the U.S. Pro Indoor for two editions, before Comcast became the sponsor of the event in 1992, effectively saving it from being discontinued. In the following years, the Comcast U.S. Indoor's prize money was reduced to less than a million dollars, preventing the creation of attractive line ups, and gaining the nickname "Comatose U.S. Indoor". In 1997, Advanta, already the sponsor of the 1971-created women's tournament of Philadelphia, the Advanta Championships, since 1995, took upon the sponsorship of the men's event, which also became the Advanta Championships. Pete Sampras won his third and fourth Philadelphia titles in the last two editions of the event, taking place on indoor hard courts at the CoreStates Center, before it was definitely discontinued in 1998.

Event names
A chronological list of this tournaments names:
 * Philadelphia Invitational Indoor Tennis Championships (1962–1965)
 * Philadelphia International Indoor Championships (1966–1968)
 * International Tennis Players Association Open Indoor (1970)
 * Philadelphia International Indoor Open Championships (1969, 1971)
 * U.S. Professional Indoor (1972–1984)
 * Ebel U.S. Pro Indoor (1985–1990)
 * U.S. Pro Indoor (1991–1992)
 * Comcast U.S. Indoor (1993-1996)
 * Advanta Championships (1997–1998)