The Derby frontman will make his senior international debut in Wednesday night's friendly against Poland at the Aviva Stadium as manager Giovanni Trapattoni takes a look some of the newer members of his squad. Sammon, who stands at 6'2", will partner West Brom's Shane Long in attack with the likes of Kevin Doyle and Jonathan Walters held in reserve.
O'Shea said: "Strength-wise, Kevin and Jon are fantastic, but I'd have to agree with you, height-wise Conor would have that advantage - and I'd think he would probably be a little bit more nimble than two fantastic players in Cascarino and Quinn."
He added: "I have played against Conor once or twice, and he's going to offer us a good physical presence up front and a threat in behind as well.
"He's a big man who is quite agile and can get about pitch quite well.
"The Polish defence, especially with Shane and Conor starting up front tomorrow, hopefully will have a very tough start to the game because from what they have shown in training, they won't let their defenders rest on the ball, the massive pressure they put on the defenders.
"Hopefully that will give us a chance to get up pitch and squeeze the game a bit more and we can take the game to Poland."
Trapattoni is hoping the pace and power of both Sammon and Long will help his team stretch the Polish defence and allow wide men Robbie Brady and James McClean to prosper.
He said: "They give us depth, they can open up the game. We have two possibilities, one to open up and develop the game, and they will also hold the ball up.
"When defenders are under pressure, they need that support. This is one of the characteristics they have."