Romelu Lukaku issued a rallying cry to his Inter team-mates after Sunday's 2-1 win over Sampdoria saw them move six points behind Serie A leaders Juventus.
Both Lukaku and Lautaro Martinez were on target in the first half at San Siro as Inter bounced back from their Coppa Italia aggregate defeat to Napoli in the semi-finals.
Antonio Conte's side were slick in the opening 45 minutes, but they took their foot off the gas after the interval and Morten Thorsby pulled one back for struggling Sampdoria.
However, the win saw Inter remain in touching distance of Juve and second-placed Lazio, who are five points above the Nerazzurri with 12 games remaining.
"It was very important to win, as from now to the end of the season it's 12 finals, they are all life or death," Lukaku told Sky Sport Italia ahead of Wednesday's clash with mid-table Sassuolo.
"Now we have to focus and get fired up for Wednesday.
"Every game is tough from now and they will not be easy for anybody. We worked really well in training, the team is in good shape physically, but we have to keep going and get even stronger, because it's going to be a game every three days."
Lukaku's 10th-minute opener took his tally to 18 goals in his first season in Serie A since 1990, a total that only Ruben Sosa, Ronaldo and Diego Milito have previously managed in their debut campaigns with Inter.
However, he was guilty of spurning two other opportunities when Inter were well on top, and Conte was frustrated that his team did not put the game to bed earlier.
"When you have the opportunity, you have to kill the opponent," added Conte, who was still frustrated with Inter's second-leg draw against Napoli eight days earlier.
"Just look at the game with Napoli: you have the opportunity to win it, it ends 1-1 and you are criticised.
"Today you had to be bad, determined, cynical ... otherwise you get in trouble. It's not that you suffer, but you go from the possible 3-0 to 2-1, knowing that the game is as vital as they will all be from here to the end."