Dustin Pedroia smacked a two-run homer, his seventh of the year, as the Red Sox won their fourth straight game after a 9-3 rout of the Rays in the series opener Friday.
The win improved the Rays to 71-73 and kept them within 4½ games of the second American League wild card, now held by the Twins.
Danny Espinosa had three singles for the Rays. He lowered his ERA to 2.76.
Matt Andriese (5-3) got just five outs, giving up eight runs - six earned - and seven hits for the Rays.
In the second inning, Boston would blow the game open.
Before his departure, Nunez collected a hit in both of his plate appearances, scoring the first run for Boston in the first inning. The Red Sox would add a third run on a groundout by Mitch Moreland.
Andrew Benintendi hit a two-run double off the Green Monster and Moreland followed up with a two-run single.
Eduardo Nunez limped out of the game after beating out an infield hit with a bruised right knee. He was held out of the game on Friday due to back spasms before returning to the lineup on Saturday. David Price (left elbow inflammation) threw two simulated innings.
He is 2-11 with a 5.06 ERA lifetime against the Red Sox - 1-3 with a 6.23 ERA at Fenway - as he and his teammates try to keep the Rays in the hunt for an American League wild card spot.
"I think we came out with good energy", Red Sox manager John Farrell said after Wednesday's game moved his team to 12-4 on the season against Toronto.
The Boston-born righty, a big Red Sox fan until he signed with the Rays in 2006, is 4-1 with a 3.34 ERA in his career in Fenway Park. Boston is 16-7 in Sale's last 23 starts and 5-1 in their last 6 games against a team with a losing record while the under is 7-2 in their last 9 games overall. In his previous six starts leading into Sunday, he had totaled a 4.54 ERA, but in four of those games he gave up three runs or less.