Paul Millsap scored 26 points and Al Jefferson went on a personal 8-0 fourth-quarter run as the Utah Jazz defeated the Phoenix Suns 100-88 Tuesday night to secure a Western Conference playoff spot.

The victory halted Utah's seven-game losing streak to the Suns, dating to March 2010.

Jared Dudley and Michael Redd scored 15 apiece for Phoenix, and Hakim Warrick had 12 for the Suns, who were without forward Channing Frye because of a shoulder injury.

The Suns won the season series but can't catch the Jazz with just one game remaining. Utah can still claim the No. 7 seed if Denver loses its final two games.

The Suns trailed 85-80 when Jefferson scored eight straight to put the game out of reach.

Jefferson finished with 18 points and 16 rebounds and is headed back to the playoffs for the first time since his 2005 rookie season. He raised his right index finger skyward then punched the air as the final buzzer sounded.

Jefferson called Tuesday's game the biggest of his career. He didn't disappoint, spinning on the baseline for a dunk then making an 18-footer to start his personal run late in the fourth. He also had two of Utah's eight blocked shots.

The Jazz return to the playoffs after missing out last year in a season that saw Hall of Fame coach Jerry Sloan abruptly resign Feb. 10, 2011, and the team trade superstar point guard Deron Williams two weeks later.

They did it despite being two games under .500 after a March 14 loss at Phoenix, playing lineups jumbled by injuries and by giving their under-21 players plenty of playing time.

Utah also has played seven overtime games, including a double-overtime loss to Toronto, triple-overtime win over Dallas and quadruple-overtime loss in Atlanta. Seventeen other games have been decided by five points or fewer.

The Jazz go into the playoffs with seven of their 14 players age 26 or younger, including four who are 21 or younger — Gordon Hayward, Derrick Favors, Enes Kanter and Alec Burks.

Though young, they are on a roll. Tuesday's win was their fourth straight and they close out the regular season Thursday at home against a Portland team they already have beaten three times.

Phoenix's regular-season finale at home against San Antonio on Wednesday could be Steve Nash's final game for the Suns. The two-time NBA MVP and eight-time All-Star will become a free agent this summer and is reportedly seeking a three-year deal.

The Jazz led by 10 points early in the third quarter after Jefferson's 17-foot jumper and were still ahead 58-50 on a dunk by Millsap following Hayward's steal.

Jefferson headed to the locker room with 7:30 left in the quarter to get two stitches above his left eye following a collision with Hakim Warrick. But he was back four minutes later just as Favors was picking up his fourth personal.

Consecutive buckets by Warrick, Dudley and Nash got the Suns to 67-66, only to see rookie Alec Burks hit a 3-pointer and make a fast-break layup.

Utah took a 73-68 lead into the fourth.

The Jazz led 49-42 at halftime thanks to a 34-20 advantage on points in the paint, 20-8 edge on the fast break and 8-3 edge in blocked shots — including five by Favors.

Three-point shooting by Shannon Brown and Redd kept the Suns close early

The Jazz led 25-19 after one, fueled by Millsap's 5-of-6 shooting and 11 points. Utah closed the quarter on a 6-0 run sparked by Josh Howard, active for the first time after missing 18 games because of left knee surgery. He entered with 2:43 left and hit his first two shots.

Suns forward Grant Hill was playing for the first time in five games after re-injuring his right knee, but started 0 for 3 for the Suns.

The Suns surged ahead 27-25 in the second, scoring the first eight points of the quarter while the Jazz missed their first seven shots. Utah then went with its big-three lineup, with Kanter at center, Favors at power forward and Millsap at small forward. The lineup produced an 8-0 Utah run.

After Jefferson subbed back in for Kanter, he and Favors had three blocks in a 54-second span as the Jazz jumped ahead 39-31.

NOTES: The Jazz announced backup PG Earl Watson won't play again until next season after right knee surgery April 17. ... Jazz SG Raja Bell was active for the first time after missing 13 games with a knee injury but did not play. ... Favors' five blocks in the first half tied his career high. ... Nash had seven assists in the first half but four turnovers.