And Coutinho, who has been impressed with the pair in training, believes they will help add a lot to the Reds' squad.
Good competition for places
Now that there is plenty of depth in attack for Liverpool, Coutinho believes that the current competition in the squad is "good" and also added that it "helps you get better".
The Brazilian explained that he is "looking forward" to playing with the club's new arrivals, calling both Mane and Wijnaldum "very good players and fast players" and saying: "The squad is very good and there are a lot of good players. I hope we can all do a good job together."
On playing with Mane in particular, Coutinho called it "very good" to train with him and joked that he's "too fast" to track. He continued that it's an attribute "you need in your game" and said the Senegal international is "a nice guy and very good player."
The signings of Mane and Wijnaldum certainly seem to complement Klopp's aggressive high-pressing system as both players are full of running and pace.
Both also seem to have an eye for a goal, which is exactly what will make this team's attack so deadly, provided that they can combine well and build a good chemistry with each other.
Liverpool's attackers look like they will certainly cause a headache for Premier League defenders this upcoming campaign.
The likes of Divock Origi, Roberto Firmino, Daniel Sturridge, Danny Ings and also the team's talisman Coutinho, will definitely by their new teammates.
In particular, the pace of Mane - of which they were victims last season against the former Southampton winger - and also Wijnaldum's all-round influence, which will add another dimension to this team.
Improving his own game
Coutinho was Liverpool's midfield maestro last season and won all the awards at the club's end of season ceremony.
However, he has remains humble and is become better and better. He looks at the matches he plays in afterwards and says that he "looks at what he can do better", adding that he is "here to learn more things" and help his team.
It'll certainly be interesting to see how Klopp manages to combine Mane and Gini with the attackers who are already at the club.
Klopp is also looking to sell Mario Balotelli and Christian Benteke, although the latter has just joined up on the team's pre-season tour of the US.
One thing is for certain, regardless of who starts for Liverpool, the team's attacking selections will cause Klopp all kinds of headaches and give Premier League defences a different type of challenge.