John Havlicek, a relentless force for the Boston Celtics over two decades and two championship eras and one of the greatest clutch stars in NBA history, died Thursday in Jupiter, Fla. He was 79.

His death was announced by the Celtics. No cause was given. The Boston Globe said he had Parkinson's disease.

Havlicek showed an unassuming but unyielding consistency throughout a 16-season, Hall of Fame career. He was known by the nickname "Hondo," given him by a childhood friend who had trouble pronouncing his surname and who thought Havlicek's strong, silent demeanor was reminiscent of John Wayne in the 1953 movie of the same name.

One play epitomized Havlicek's reputation as the pre-eminent hustle player of his time and possibly, as many older Celtics fan would argue, of all time.

On April 15, 1965, the Celtics were clinging to a 110-109 lead in the decisive seventh game of the 1965 Eastern Conference final playoff series. With five seconds remaining, center Bill Russell's inbounds pass from under the 76ers' basket hit a guide wire overhead, giving the 76ers the ball and a chance to win the series.

Guarding Chet Walker, a star forward for Philadelphia, in the area near the free-throw line, Havlicek began silently ticking off the five allotted seconds that 76ers guard Hal Greer had to inbound the ball. Then, at the count of four, Havlicek peeked back at Greer, who had just tossed the ball in Walker's direction.

Havlicek reached and tipped the pass to Celtics guard Sam Jones, who then dribbled out the clock to cement the Boston victory, setting off pandemonium in Boston Garden. Havlicek was hugged by Russell, mobbed by fans and stripped of his jersey.

The play was immortalized by longtime Celtics radio broadcaster Johnny Most, whose call — "Havlicek stole the ball!" — became enshrined in every highlight reel of the team's glorious history.

"Red Auerbach always said, 'Look for an edge,' " Havlicek recalled in a 2015 NBA video marking the 50th anniversary of the steal, referring to the Celtics' organizational patriarch and nine-time champion coach. "I did what I was supposed to do. I never realized it would last this long, but it is everlasting."

Spanning eras that included Russell and Dave Cowens, star center of the 1970s, Havlicek was part of eight Celtics championship teams in all, never losing in an NBA Finals. He was also a standout at Ohio State when the Buckeyes won an NCAA title in 1960 and reached the championship game in two subsequent seasons.

It was with the Celtics that Havlicek developed his game as a unique two-position player — small forward and shooting guard. Early in his career, he raised the visibility and value of the sixth man, before becoming a starter when Russell, a player-coach, retired after the 1968-69 season and Tom Heinsohn, a former teammate of Havlicek's, took over as coach.

Havlicek was voted to the All-NBA team four times, the second team seven times and the defensive first-team five times. Russell, who is considered to have been the most indispensable Celtic of all, called Havlicek "the best all-around player I ever saw."

Havlicek, who averaged 20.8 points for his career, played in more games (1,270) for Boston than Russell, scored more points (26,395) than a later Celtics star, Larry Bird, and handed out more assists (6,114) than any other Celtics playmaker except Bob Cousy.

But when he joined the Celtics as a rookie in 1962 as the seventh pick of that year's college draft, Havlicek was mainly a tenacious defender with an indefatigable work ethic. Some teammates, Cousy included, doubted he would amount to much.

"He didn't really shoot from the outside or dribble that much," said Heinsohn, who had played alongside Havlicek for several seasons in Boston. "But he was like a wide receiver in football, and he would run and catch long passes from Cousy for layups."

Havlicek never did stop moving, all the way to April 9, 1978 — the last time a Celtics player wore No. 17.