Speaking before their final Group B match against Spain at the Estadio Castelao, the affable Keshi said the experience had proved invaluable for the African champions even if they are eliminated on Sunday.
"Yes I have seen the good, the bad and the ugly sides of my team and seen enough to help me take the team to the next level. I have learnt a lot and am very happy to be here playing against quality sides," he told reporters.
Nigeria, who beat Oceania champions Tahiti 6-1 in their opener before losing 2-1 to South American champions Uruguay on Thursday, must defeat Spain and end their unbeaten 24-match run to have any realistic chance of reaching the semi-finals.
However, even a win may not be enough if Uruguay run up a huge score against amateurs Tahiti as expected.
After the Spanish hammered Tahiti 10-0 and Uruguay beat Nigeria, the dice seem loaded in favour of world and European champions Spain and Uruguay going through to the last four.
But even if Nigeria go out as looks likely, Keshi will go home much the wiser as he prepares for a World Cup qualifier against Malawi in September which will decide which team goes through to the final round of African qualifiers.
"I have seen our level of professionalism and have seen our concentration, our level of preparedness before and after and during the games," he said.
"I have looked at my coaches and seen how they react with the players and have looked at the other teams as well. We do have a young team here, but these players have the heart and the quality to play and anything can happen when it is 11 against 11."
Asked if his team mates were scared of playing Spain, who were last beaten in a competitive match when they lost their opener to Switzerland in the World Cup in South Africa three years ago, Nigeria captain and goalkeeper Vincent Enyeama bristled with indignation.
"I am sorry to say this to you, but I do not think there is one single player in our team who is scared," he said.
"The clubs in Spain might be bigger, but we are proud of our league and we are proud to wear our colours. We are not afraid of Spain, but we respect them. Thank You."
Keshi responded: "Of course they are a good team, they are the world and European champions but we are also a good team and we are the African champions, and we are proud to represent our continent. a great continent, so have some respect for us at least."
Nigeria beat Spain in their only previous senior meeting, scoring a 3-2 victory in the group stage of the 1998 World Cup in France.
"Spain had a great team then with players like Raul and Kiko and Andoni Zubizarreta and they have a great team now. Football is more scientific now, it is harder today, but that victory had a great impact in Nigeria at the time and we will be looking to beat them again tomorrow," added Keshi.