Durant, who had at least 40 points in three of his previous four games, added 24 in the Thunder's fourth victory in five games. Russell Westbrook scored 19, including an 11-footer that put Oklahoma City up 107-103 with 34 seconds to go.
"It wasn't just a one-man, two-man game tonight," Durant said. "It was everybody."
Vince Carter scored a season-high 33 for Phoenix, but missed three long-range jumpers down the stretch as Oklahoma City outscored the Suns 12-5 over the last 2½ minutes. No other player scored more than 13 for the Suns.
Carter was 1-of-7 shooting in the fourth quarter, missing his last five attempts.
Oklahoma City tied it at 97 after Hill was whistled for a foul on Durant. Hill and Nash drew technical fouls from referee David Guthrie for complaining about what replays showed to be a dubious call. Durant made only two of the four free throws, though, and Hill's 3-pointer with 3:22 to play put Phoenix back ahead 100-97.
Ibaka's tip-in cut it to 100-99, then Nash made two free throws to put Phoenix ahead 102-99 with 2:38 to go.
The Thunder followed with an 8-1 run, capped by Westbrook's jumper in the lane. Nash's driving layup with 16 seconds to go cut it to 107-105, then Durant and Westbrook put the game away at the foul line, despite loud complaints from Phoenix coach Alvin Gentry that Durant should have been called for traveling before he was fouled.
"Just give them the game," Gentry complained.
Durant, the NBA's leading scorer, made just 2 of 7 shots in the second half, one of them on an offensive basket interference call against Frye.
Ibaka, in his second NBA season from the Republic of the Congo, scored six in the decisive late surge, including a sweet turnaround 11-footer.
"Serge is a big part of what we do and our success," Thunder coach Scott Brooks said. "He works and continues to get better. His energy and focus tonight was as well as he could possibly play. He made nearly every shot and they were all big shots down the stretch."
Down 69-64 after Durant's only basket of the third quarter, Phoenix outscored the Thunder 19-7 to go up 83-76 with 2:06 left in the period. The last 12 points of the run came on 3-pointers, two by Carter and one apiece by Hill and Nash. Phoenix led 87-80 entering the fourth quarter.
"Obviously we've got to do a little bit better job defensively in the fourth quarter," Gentry said, "but we also missed a bunch of shots that could've given us a little separation or could've kept us right there in the game."
Carter made all five of his shots, two of them 3-pointers, in a 15-point first quarter.
Neither team led by more than five in the second quarter and the Thunder were up 63-60 at the half.
After speculation that Nash could be named to the NBA All-Star game to replace injured Yao Ming, the spot went to Minnesota's Kevin Love. The Suns are without a player in the game for the first time since 2004. ... Phoenix guard Goran Dragic missed his third game in a row after cutting his left foot stepping on a piece of broken glass at his home, requiring nine stitches. ... Durant is his franchise's first All-Star starter since Gary Payton in 1998. ... Carter's previous high this season was 29 against New York on Jan. 7.