Sainsbury, who has joined Inter on loan from parent club Jiangsu Suning, watched on as Inter produced a committed display, despite lacking some of their brightest attacking talents.
Ivan Perisic and Mauro Icardi were both suspended after the tempestuous 1-0 defeat to Juventus the previous week, but Stefano Pioli's combination of Joao Mario, Rodrigo Palacio and Eder in attack quickly paid off when the Italy striker put his side ahead after 14 minutes.
Eder turned provider for Antonio Candreva for Inter's second, and Pioli will have been encouraged by the way his players applied themselves in a tricky fixture against well-organised opponents as victory maintained their place within six points of third-placed Napoli, despite having gone into the game on the back of successive defeats to Lazio in the Coppa Italia and Juventus in Serie A.
Empoli, still eight points above the drop zone, showed themselves capable of competing with the league's top sides when it comes to possession in midfield, but their reliance on veteran striker Massimo Maccarone in attack was not enough to threaten Inter's defence.
In the absence of the suspended Icardi, Pioli started with Palacio as the spearhead of his attack and the veteran striker was denied the opening goal when his header was saved acrobatically by Lukasz Skorupski in the Empoli goal after 10 minutes.
Inter cranked up the pressure on the Empoli goal and it paid off after just 14 minutes when Candreva's deflected cross looped up in the air and Palacio headed it across the face of goal for Eder to bundle the ball home with his chest.
Omar El Kaddouri curled a shot towards goal as Empoli's neat passing in midfield yielded a chance for the visitors but Samir Handanovic parried it away, and at the other end Roberto Gagliardini was denied his first goal in Serie A when Skorupski turned his powerful close-range drive over the crossbar.
Having worked hard to stay in the game in the first half, Empoli should have drawn level early in the second when Rade Krunic went through on goal and only a good one-handed save by Handanovic kept his shot out.
That miss proved crucial, as seconds later Inter doubled their lead when Eder's sublime cross found Candreva at the far post and he instinctively fired a first-time shot into the net to make it 2-0.
Maccarone went one-on-one with Handanovic but failed in his attempt to chip the goalkeeper, and Pioli sent on Gabriel Barbosa for the final 20 minutes as Inter sought to wrap up the victory.
Daniele Croce tried a spectacular volley that Handanovic parried away as Empoli refused to lie down, while Pioli used the last 10 minutes of the game to hand a Serie A debut to 17-year-old striker Andrea Pinamonti, who tested Skorupski from range before ending his first appearance on a winning team.
Key Opta stats:
- Eder has scored a goal in each of his last three Serie A home appearances.
- Antonio Candreva has found the net in each of his three Serie A home games played against Empoli, two for Lazio and one for Inter.
- Inter have won eight consecutive Serie A home games for the first time since May 2011, when they reached 13 in a row.
- The Nerazzurri have found the back of the net in each of the last 21 home games in the top flight.
- Empoli have picked up just a point over the last three Serie A match-days, conceding seven goals in the process – they had shipped only two over the previous six matches.
- Inter fired eight shots on target, only in three other games have done better this season in the league.