Robertson came on in the eighth inning with the game tied at four to face Stephen Head and Brian Pettway, who had each homered earlier in the game.
The Crimson Tide snapped the 4-4 tie with a run in the ninth inning of junior left-hander Stephen Head, who was moved out of the starting rotation and into the bullpen for the Alabama series.
Senior third baseman Rocky Scelfo drew a lead off walk and moved into scoring position on sophomore second baseman Greg Paiml's sacrifice bunt. Sophomore center fielder Emeel Salem doubled to left field to score Scelfo with the winning run.
Earlier, Scott tied the game with a solo home run in the top of the eighth inning. Scott homered in consecutive at bats in the sixth and eighth innings for his first career multi home run game.
Scott, who went 3-for-4 with two home runs and two RBI in the win, extended his hitting streak to 19 consecutive games with a fourth inning single.
"This was a good road win and Gabe Scott swung the bat really well," Alabama head coach Jim Wells said. "I'd love for someone in front of him to get hot right now, because he is really swinging the bat well.
"We had a lot of guys really step up. Paiml had a good game, with some really good at-bats. Scelfo drew the walk. Guys are getting on base now and making things happen. I'm proud of the way the guys came back. We are showing that ability against quality teams."
Ole Miss (21-9, 5-5 SEC) scored two runs in the bottom of the sixth inning to take a 4-1 lead and was one the verge of knocking UA starter T.J. Large and the Crimson Tide out of the game.
But after back-to-back walks to load the bases, Large got freshman shortstop Zack Cozart to hit into the inning-ending double play and the Rebels were shut down afterwards.
Large worked a seven innings and allowed four runs and four hits, with four walks and five strikeouts for the no decision.
Robertson (5-2) pitched two scoreless innings in relief for his fifth win of the year. The Tuscaloosa native retired all six batters he faced, with three strikeouts.
Head (5-2) took the loss for Ole Miss with two innings in relief. He allowed one run and two hits, with two walks and three strikeouts.
The Rebels took a 1-0 lead in the second inning when junior right fielder Brian Pettway jumped on a hanging breaking ball and slammed it over the left-center field fence.
Ole Miss took a 2-0 lead in the fourth inning when third baseman Chris Coghlan was hit by a pitch and scored when Mark Wright smacked a two-out double that was dropped when right fielder Morrow Thomley slammed into the wall in right-center field.
Scott launched his first home run of the game in the top of the sixth inning to pull the Tide to within a run at 2-1.
Ole Miss answered with two runs in the bottom of the inning when Head drilled an opposite field, two-run home run to left center for a 4-1 lead.
Alabama scored twice in the seventh inning to make it a 4-3 game. Sceflo started the two-out rally with a base hit up the middle and Paiml drew a walk after being down in the count 0-2. Salem followed with a base hit up the middle to score Scelfo and senior designated hitter Allen Rice followed with a single through the right side to score Paiml and make it a one-run game.
The series continues on Saturday with a 4 p.m. game at Swayze Field. Alabama senior left-hander Brent Carter (4-2, 3.18 ERA) will take the mound for the Crimson Tide against Ole Miss junior lefty Matt Maloney (4-1, 0.89 ERA), who will be making his first SEC start of the year.
*Alabama scored all five runs in its final four at-bats for its 12th come-from-behind win of the season.
*Alabama improved to 5-5 in one-run games this season, while Ole Miss falls to 3-6.
*The Crimson Tide had not won the series opener with Ole Miss since the 2000 season. In addition, Alabama had lost its last two series openers with Ole Miss by a combined 21-3 score, including last year's 11-1 loss in Tuscaloosa.
*Alabama has won back-to-back games over No. 4 LSU and No. 9 Ole Miss by identical 5-4 scores. This is the second time this season the Crimson Tide has won back-to-back games by the same score. UA opened SEC play with back-to-back 5-3 wins over Kentucky on Mar. 18-19.
*Alabama has seven SEC wins in its first 10 games. The Crimson Tide won only 10 games all of last season.
*Alabama is 8-1 (.889) in Large's nine starts this season.
*Alabama senior LF Gabe Scott had three hits against Ole Miss, including two solo home runs. He put the Crimson Tide on the board in the sixth inning with a solo home run to left-center field. Scott tied the game with a solo shot, measured at 375-feet, to right field in the eighth inning.
*The Lake Charles, La., native extended his hitting streak to 19 games with a fourth-inning single. During the hitting streak, Scott is batting .435 (27-for-62) with four home runs, 12 RBI and 12 runs scored. He has raised his season batting average 197 points since the streak began on Feb. 25 against Duquesne.
*Scott has four home runs in his last four games for Alabama.
*Alabama has homered in four straight games for the second time this season. UA also hit a home run in four straight games from Mar. 11-16. Bama has also homered in four straight SEC games for the first time this season.
*Ole Miss RF Brian Pettway slammed a solo home run in the bottom of the second inning to snap junior RHP T.J. Large's streak of 17 consecutive scoreless innings streak. Large had not allowed a run since the first inning of the Vanderbilt game on March 25. After the first inning run, he blanked Vandy over the final 6 2/3 innings and then fired a nine-inning shutout against No. 4 LSU in his last start on April 1.
*Pettway's home run came on a 3-2 pitch and traveled 397 feet to left-center field.
*Senior OF Matt Grooms collected a pinch-hit single in the sixth inning for the Crimson Tide. As a pinch-hitter this season, Grooms is a 4-for-8 (.500) and has one hit in each of his last two pinch-hit opportunities.