The Colombia international has stressed the Nerazzurri will do their utmost to get the full three points, while Javier Zanetti has praised the club's attackers
Andrea Stramaccioni's men initially struggled against the Blucerchiati, as Gianni Munari gifted the visitors a 1-0 lead at half-time.
However, goals from Diego Milito, Rodrigo Palacio and Guarin swung the match in Inter's favour, before Eder pegged one back well into stoppage time.
"We played an excellent match against a tough side, we got the win and now let's think about Juve," Guarin told Inter Channel.
"Now we can focus on Juventus and we'll fight to win the match. We're slowly getting to where the coach wants us to be, by working hard and winning games."
Meanwhile, experienced defender Javier Zanetti has insisted Inter will try and play their own game against the Scudetto holders, while praising the Nerazzurri's attackers.
"We'll go to Juventus as a team on the up and will look to play our own game. We know we're playing a great team, let's hope it's a good game of football.
"We have three excellent forwards who are all doing their bit, they're all stars and we're lucky enough to enjoy their ability, both in training and matches. I hope they continue in this vein."
Inter currently sit second in the Serie A table, trailing the Bianconeri by four points.