Bell supplied the grit with a surprise start despite a slightly torn calf muscle, and his teammates took care of the offense in a 106-86 rout of the Dallas Mavericks on Tuesday night.
"Well, I guess we're not done yet," Suns coach Mike D'Antoni said.
Tied at two games apiece, the series returns to Dallas for Game 5 on Thursday night.
Leandro Barbosa, coming off a poor performance as a starter in place of Bell in the Suns' Game 3 loss, scored 24 points on 10-for-13 shooting.
Boris Diaw added 20 points, including two emphatic fourth-quarter dunks that helped the Suns build a 25-point lead.
Bell had missed the past two games with a slight tear in his left calf, and all indications had been that he would sit out this one, too.
"I've been to war all season with these guys," Bell told TNT at halftime. "I wasn't going to watch tonight."
He had only nine points but gave Phoenix some much-needed intensity in 32 minutes of play.
"Half our team is a bunch of quiet guys," Nash said. "He gives us another guy that opens his mouth once in a while, gives us some toughness, some bravado. I can't say enough about how much his personality means to our team."
D'Antoni called Bell "a team guy. He's never asked for anything. He's been a team guy. He just plays hard every night. And, you know, to be able to coach a guy like that is precious."
Dirk Nowitzki managed only 11 points for the Mavericks on 3-for-13 shooting, breaking a string of 42 games when he's scored at least 20 points.
It was his lowest-scoring game all season and the first time he's scored fewer than 25 points in the Mavs' eight games against Phoenix this season.
"We turned the ball over way too many times, especially early," Nowitzki said, "and we made mistakes all over the place."
Josh Howard led the Mavericks with 16 but left with an apparent shin injury with 5:47 to play. Dallas coach Avery Johnson said afterward that "Josh is fine."
It was a rough night all the way around for Dallas.
Johnson drew a technical foul early. His wife, Cassandra, got into a nose-to-nose argument with a fan, with Mavericks owner Mark Cuban coming to her defense. Security personnel escorted the fan away.
"You know, I can point to a lot of things that were very disgraceful about the game," Johnson said, "but we lost."
He would not elaborate.
The Mavericks said Barbosa, rather than Bell, was the biggest factor.
"He was a tough little guy today, and we've got to make sure we handle him a lot better next time," Nowitzki said.
Phoenix never trailed after the first quarter. The Mavericks stayed close, despite the shooting woes of Nowitzki, until the Suns blew it open with a 20-4 outburst at the end of the third quarter and start of the fourth.
Jason Terry's second 3-pointer of the quarter cut the Suns' lead to 67-65 with 3:49 to play in the third. But Dallas went cold and the Suns finished the quarter with a 12-2 run. Five Phoenix players scored in the surge, capped by Marion's stuff with 37 seconds to go that put the Suns ahead 79-67 entering the fourth quarter.
Diaw dunked over Nowitzki for a three-point play to start the fourth quarter to make it 82-67. Another dunk by Diaw ended the surge and put Phoenix firmly in control for good, 87-69, with 10:14 to play.
The Suns shot 54 percent, including 7-of-15 on 3-pointers, compared with 42 percent for the Mavericks.
Terry and Adrian Griffin added 13 points apiece for Dallas, which regained the home-court advantage in the series with its 95-88 victory Tuesday night in Phoenix.
With a chance to go up 3-1, then close it out at home, the Mavericks fell flat.
For the first half, though, they weren't in bad shape, despite some awful statistics.
The Suns shot 59 percent, Nowitzki was 1-for-7 and Terry 1-for-5, and still the Mavericks were down only 51-46 at the break.
Consecutive driving layups by Barbosa put Phoenix ahead 49-40 with 3:24 left in the half. Howard converted a three-point play, Terry dunked from the baseline, then made one of two free throws to cut it to 49-46 with 32 seconds left before the half.
Nash made a 12-footer, then Nowitzki missed a jumper at the halftime buzzer and Phoenix led 51-46.
The Suns' Kurt Thomas, sidelined since Feb. 22 with a stress fracture, played the final 5:47. ... The Suns, an 84 percent free throw shooting team in the playoffs, were 13-of-21 at the line. ... Diaw has four consecutive 20-point games for the first time in his career. ... It was Dallas' most one-sided loss in these playoffs.