PHILADELPHIA (CBS) -- One of the NBA all-time greats is calling it quits.

San Antonio Spurs power forward Tim Duncan announced his retirement on Monday.

Duncan, 40, retires after five NBA titles, two NBA MVP awards, and 15 All-­Star appearances. Many people consider Duncan to be the greatest power forward in NBA history, including 94WIP's Ike Reese.

"The Big Fundamental" retires with averages of 19.0 points, 10.8 rebounds, 3.0 assists and 2.2 blocks per game. He was an NBA All-Defensive First Teamer eight times and is only the third player in NBA history to win 1,000 career regular season games.

Duncan sits 14th all time with 26,496 points, sixth in rebounds with 15,091, and fifth in blocks with 3,020.