PINE TWP, Allegheny County — A former standout basketball player at Knoch High School who went on to coach girls varsity basketball at Pine-Richland High School was arrested Friday for allegedly having a sexual relationship with one of his players.

Cliff Foster, 33, of Wexford is in the Allegheny County Jail on $20,000 bail.

Superintendent Brian R. Miller in a statement said the district became aware of a report filed Thursday with the Department of Human Services Office of Children Youth and Families.

Foster was only employed as a coach.

“The district is shocked by the nature of the allegations,” Miller said in the statement. “The district has issued an immediate suspension of the coach pending the outcome of the investigation.”

Miller added the district believes the alleged abuse to be an isolated case.

The Northern Regional Police Department and CYS are investigating.

While at Knoch, Foster was named Butler Eagle Boys Basketball Player of the Year for the 1999-2000 season, averaging 19.7 points and 10.3 assists per game as the team’s point guard.

He went on to a standout basketball career at La Roche College, where he set school records of 636 career assists, 201 assists in one season and 238 career steals. During his senior season, he led La Roche to its first Allegheny Mountain Collegiate Conference championship.

Foster was hired as girls basketball coach at Pine-Richland before the 2012-13 season. His three-year record there is 40-32. Pine-Richland was 21-6 last season — its best girls basketball record in years — and lost to Bethel Park in the WPIAL quarterfinals.

Foster, who also was charged with corruption of a minor, has a preliminary hearing scheduled for Oct. 28 at the office of District Judge William Wagner.