The 28-year-old striker sent a message to both Magpies owner Mike Ashley and England boss Fabio Capello on Saturday when he came off the substitutes' bench following his latest injury lay-off and, as he has done so many times throughout his career, proved to be the match-winner.
Keegan later admitted that in an ideal world, his £17million man would have played no more than 15 minutes of the victory over Bolton having spent pre-season working his way back from a bout of mumps and a series of niggling injuries.
But with Obafemi Martins and Damien Duff back in the treatment room with a groin problem, Mark Viduka still on the comeback trail and Alan Smith not fully fit, manager and captain have a big decision to make between them ahead of tomorrow night's Carling Cup second-round trip to Coventry.
Owen said: "Now I've just got to make sure I am fit and healthy for the next few games.
"We will discuss how long I'm going to play against Coventry, but obviously Oba Martins has now got an injury and we will just have to wait and see.
"I had a bad illness over the summer, but I could have been really unlucky and had it during the season. Thankfully, I've just missed one game, though it seems like I have been away for ages."
But Keegan might have preferred to have kept Owen under wraps until Saturday's Barclays Premier League visit to Arsenal.
However, an appearance at the Ricoh Arena would give the player another chance to emphasise just why his manager is so keen to tie him up in a new contract just hours ahead of scheduled discussions on the matter with owner Mike Ashley.
Owen's winner against Bolton was his seventh headed goal in his last 12, quite an achievement for a striker who stands just 5ft 9in tall.
He said: "Your game changes over the years. When I started, I suppose I scored one in 50 headers, and now every other goal seems to be from my head.
"You learn different things as you get older."
Keegan was fulsome in his praise of Owen after seeing him edge his side to victory over a determined Bolton, and the manager knows Tuesday night's test will prove little easier.
He said: "It's going to be a tough place to go, but it should be a good game.
"Coventry have started off well. I know they were beaten on Saturday, but they started off with six points from the first two games and they have got a guy who I really respect in charge there, Chris Coleman, who I brought to Fulham.
"They are a club that are looking to build and go places, and their ambition is to be in the league we are in.
"It is a good test for us in a competition we will take very seriously."
Keegan came closer than most of the club's recent managers to lifting a trophy for the first time since 1969 during his first spell in charge at St James' Park, and he knows just what is at stake in the Carling Cup.
He said with a smile: "It is one of two chances, if we are honest. We can win the FA Cup and we can win the Carling Cup, they are definitely the two chances.
"At the moment, we have got a chance of winning the league - that might peter out as the season goes on, it depends on how we play."