The Republic of Ireland will enter their crucial away tie with Estonia this Friday without one of their best and most experienced players.

Former Manchester United defender, and current Sunderland captain, John O'Shea will miss the trip to Estonia because of a hamstring injury.

The 30 year old from Waterford has been capped an incredibly 70 times for his country and has been a stall-worth in the team over the past few seasons. O'Shea's versatility had seen him move to right back after the emergence of Sean St. Ledger in the center during the most recent campaign.

O'Shea's ability to play at the top level, not to mention his experience, would have been a major asset as Giovanni Trappatoni's side looks to shut out Estonia in Talinn.
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The fact that O'Shea was no longer playing center back will aid the team as they look to overcome his loss. The solidity that is provided by St. Ledger and Richard Dunne in the middle, in front of Shay Given, will allow the team to slot in a replacement for O'Shea on the outside rather than in the middle.

That replacement presumably will be Stephen Kelly.

Kelly has regularly replaced O'Shea at right back for the republic and even captained the team when they entertained Uruguay in the Aviva stadium recently.

At 28 years of age, Kelly has 25 caps to his name. He is undoubtedly a talented defender but has struggled with consistency throughout his career. As a result he has bounced around in various loan deals and transfers leading to him representing seven clubs in the past decade or so.

In recent times however, despite not playing regular club football, Kelly has been a reliable servant to the Irish side over the past year or two.

The maturity in his play is palpable. As far as intelligence and positional sense, Kelly will not be someone that Richard Dunne has to keep one eye on. He is more than willing to dive into a strong challenge and doesn't shy away from the moment.

He may not get many opportunities to cross the ball or get down the wing on Friday, but the ability to do so is there should the opportunity arise.

Ireland will enter this tie in Talinn with some significant players missing, such as John O'Shea and Kevin Doyle, but the stability and depth is definitely there for the team to overcome those issues.

Stephen Kelly may not be a star, but Giovanni Trappatoni hasn't brought Ireland to this point by relying on stars. Trappatoni has picked his teams, whether you want him to or not, based on reliability, stability and consistency.

Kelly can definitely be considered one of those players at this stage in his career.

Tweeting @Cianaf