Fournier scored 26 points, including a couple of late 3-pointers, and the Magic beat San Antonio 111-109 on Friday night to hand the Spurs their fourth straight defeat.
Ross had 10 of his season-high 20 points in the fourth quarter to help the Magic win consecutive games for the first time this season.
"That's what T-Ross does, time and time again, when we win games," said Aaron Gordon, who had 14 points and eight rebounds. "He steps up and makes big shots. We needed them tonight badly."
Fournier's 3-pointer with 1:15 remaining put the Magic ahead to stay. He shot 5 of 6 from behind the arc in his highest-scoring game of the season.
"When T-Ross and I both make shots, it just spreads the floor and it gives us more opportunity," Fournier said. "Then the paint is open for Vuc (Nikola Vucevic). It's the lineup we mostly ended games with last year and it's the lineup we are comfortable with."
DeMar DeRozan scored 21 for the Spurs, who shot 50.6 percent from the field but gave up 64 points in the second half and were outrebounded 48-41.
"I think the difference in the game was we gave up too many offensive rebounds (14)," DeRozan said. "We couldn't get the rebounds when it counted and they did. They executed on those, and other than that it was a one-possession game."
A flagrant foul call helped the Magic maintain their lead in the final seconds.
After Trey Lyles' 3-pointer cut Orlando's advantage to 107-106 with 18 seconds left, Gordon drew a foul on DeRozan with 13.9 seconds remaining that was upgraded to a flagrant after a replay review. Gordon made the free throws and the Magic kept the ball, enabling Vucevic to add another foul shot for a four-point edge.
A 3-pointer by Bryn Forbes with 4:17 left in the second quarter put San Antonio up 50-34, the largest lead for either team.
The Spurs shot 53 percent in the first half and led 56-47 at halftime.
Orlando ran off 12 straight points early in the third quarter and took a 69-66 lead on a 3 by Fournier.
Spurs: Dejounte Murray played 21 minutes but will sit out Saturday night against Portland, part of the plan for his recovery from knee surgery a year ago. ... Aldridge missed all six of his shots in the first half. ... The Spurs have given up 122 points per game during their losing streak.
Magic: F Jonathan Isaac did not play after rolling his right ankle Thursday night during the unveiling of the Magic's City-Edition uniforms at Disney World. "We were taking pictures, just shooting around and I got a little careless," said Isaac, the first Orlando starter to miss a game this season. He hopes to play Sunday against Washington. ... F Al-Farouq Aminu grabbed 13 rebounds in his first start for the Magic. ... G Michael Carter-Williams was called for three fouls in 13 seconds late in the first quarter. ... Vucevic shot 4 for 16.
Magic coach Steve Clifford on Isaac's bizarre injury: "People always say I shouldn't leave guys in at the end of the game when we have a 12-point lead because somebody might get hurt. Hey, somebody could get hurt walking down the hall. It happens all the time."
Spurs: Host the Portland Trail Blazers on Saturday night.
Magic: Host the Washington Wizards on Sunday night.
More AP NBA: https://apnews.com/NBA and https://twitter.com/AP-Sports
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