Brazil forward Coutinho has called for his Liverpool teammates to keep their focus in order to achieve the club's "big objectives" this season.
The 24-year-old recently returned from an ankle injury and came on in the 61st minute in the 1-1 draw on Sunday away to Manchester United at Old Trafford.
Despite taking a lead through a James Milner penalty, United managed a late equaliser through Zlatan Ibrahimovic.
Coutinho reckons his team need to rediscover their form to curb a four-game winless streak ahead of Wednesday's FA Cup clash against Plymouth Argyle.
"We have to keep working together because the season is very long. We have big objectives to realise this season," Coutinho told Sky Sports.
"The confidence [of a good result] brings good feeling, tells us that we have to keep working hard.
"This season promises to be very important for us and Liverpool have to keep playing well."
The Brazilian was also quick to thank manager Jurgen Klopp for instilling a newfound sense of confidence at Anfield this season.
"He is a great manager," Coutinho added.
"He has changed the mentality in our team, we have become much stronger in defence, and we'll keep working together."