The focus will be even more on Cristiano Ronaldo on Tuesday night as he wins his 100th cap for Portugal in their World Cup qualifier against Northern Ireland in Porto.

The Real Madrid forward has scored 37 goals since he made his debut in 2003 and who would bet against him adding to that tally against a fragile Ireland side?

While the Portuguese are a healthy second in Group F with six points from three games, Michael O'Neill's men have one point from a possible six and are expected to struggle inside the Estadio Do Dragao.

What's worse is that they are in the midst of an injury crisis as Alex Bruce, Grant McCann, James McPake, Joe Dudgeon, Shane Ferguson and Martin Paterson have all withdrawn from the squad. Danny Lafferty, Lee Hodson and Rory McArdle have been called up as replacements.

Meanwhile, Raul Meireles and Fabio Coentrao are sidelined for the hosts with Real Betis full-back Nelson coming into the fold in place of Coentrao.

Current form:

Portugal: WLWWWL
N. Ireland: LLLDLD

Possible lineups:

Portugal: Patricio; Alves, Pepe, Pereira, Nelson; Moutinho, Micael, Veloso, Nani; Ronaldo, Postiga

N. Ireland: Carroll; Baird, Hughes, Evans, McAuley, McGivern; Carson, Davis, Norwood, Clingan; K Lafferty

Sports Mole says: 3-0