Sanchez teed up Ashley Young to volley Inter ahead at San Siro after just five minutes and the Chile forward dispatched a spot-kick to double the lead following a foul on Victor Moses.
Inter hammer Brescia to stay in Serie A title hunt
Alexis Sanchez scored a penalty and set up two goals as Inter Milan thrashed relegation candidates Brescia 6-0 on Wednesday to keep their slim Serie A title hopes alive.
Danilo D'Ambrosio powered in a third just before half-time from a looping cross by Young, with Roberto Gagliardini rising to head home a Sanchez free-kick as Inter grabbed a fourth on 53 minutes.
Christian Eriksen bagged his first Serie A goal since his January move from Tottenham, forcing in from point-blank range after an excellent Jesse Joronen save denied Romelu Lukaku.
Antonio Candreva completed the romp two minutes from time with a crisp low drive into the corner as Inter clawed back to within eight points of leaders Juventus with nine games still to play.
Brescia, who were again without Mario Balotelli due to an ongoing contract dispute, dropped to the foot of the table beneath SPAL on goal difference. They remain eight points from safety and are winless in 14 games.
Cagliari drew 1-1 at Bologna as Giovanni Simeone struck early in the second half for the visitors following Musa Barrow's goal in first-half stoppage time.
AC Milan welcomed back Zlatan Ibrahimovic from injury ahead of their visit to SPAL later on Wednesday.
Milan have won both league games since the Serie A restart and victory would send Stefano Pioli's side level with Napoli in the battle for the final Europa League berth.
Juventus maintained their four-point lead at the top on Tuesday after strolling to a 3-1 win at Genoa that kept chasers Lazio at bay despite their 2-1 comeback victory at Torino.
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