Keown said: "I'm very proud to be given the opportunity to captain my country - but very quickly we've got to get on with the job of rescuing a very bad start to our World Cup campaign.
The Arsenal central defender, handed the captain's armband by caretaker coach Howard Wilkinson, urged to kick-start their World Cup qualifying campaign into life against Finland in Helsinki on Wednesday.
Keown will lead his country for the first time after skipper Tony Adams and vice-captain David Beckham were both forced to pull out of the squad through injury in the last 24 hours.
The Arsenal ever-present was adamant the players had lost "a special friend" with Keegan's departure but insisted everyone must now look forward and start to repair the damage after Saturday's 1-0 defeat by Germany at Wembley.
Keown said: "I'm very proud to be given the opportunity to captain my country
- but very quickly we've got to get on with the job of rescuing a very bad start
to our World Cup campaign.
Tough match
"It will be a tough match and Finland feel it is a game they can win so we have to pull together very quickly as a group and take things forward. As the captain I hope I can form a link between the players and staff and lead from the front on the pitch.
"I think morale is picking up now. Kevin Keegan is a special person and a lot of people have been down and disappointed but the world of football moves on very quickly and people get on with the job.
"We have not had a lot of time to sit around pondering about the situation. We've got a real task ahead of us but there are still plenty of points to be won and that's what we're going for."
Keown insisted being elevated to skipper would not alter his approach on the pitch.
He said: "I like to feel I will react as I do every week. The fact I am not wearing the armband then doesn't stop me from trying to lead, trying to organise and do the job as I feel fit.
"Perhaps when you are captain it lifts your profile a little bit and it becomes more visible but I have always led in the same way."
No great surprise
Keown admitted that Keegan's departure had not come as a great surprise given his past record of making spur of the moment decisions such as when he quit Newcastle.
He said: "There was no real indication that he was going in the build up to this match and he was very positive as he has been throughout with us.
"But we knew that in the past he has made decisions when emotional so you
have to say it wasn't so much of a shock from that point of view."
Wilkinson told Keown that he was replacing Adams as skipper during the team's flight to Helsinki on Monday evening.
He said: "I think the aeroplane gained extra altitude after I told Martin! I took things into consideration like there being a number of club captains already in the team and that David Seaman had already led England.
"But Martin Keown has really established himself now in everyone's eyes and his qualities are very similar to Stuart Pearce. He has got the qualities we need, that every team needs particularly at times like this."