Robbie Keane has been named in the Republic of Ireland squad for the friendly against Oman and the opening World Cup qualifier against Serbia which follows it. The 36-year-old LA Galaxy striker, who has 145 senior international caps to his name, has been included in a 28-man party amid speculation that he will announce his retirement from international football after the Oman game on August 31.

Fellow veteran John O'Shea has also been included, although he will be assessed after suffering a hip injury during Sunderland's 2-1 derby defeat by Middlesbrough on Sunday, as will Everton's Seamus Coleman and midfielder Jeff Hendrick, ahead of the game in Belgrade on September 5.

Manager Martin O'Neill said: "After the excitement of UEFA Euro 2016, it seems as if we had little time to enjoy some excellent performances during that tournament.

"The World Cup qualifying campaign is already upon us and we have a difficult set of fixtures in the coming months.

"The visit of Oman to the Aviva Stadium reminds us of the game they played in Dublin two years ago. That took place immediately before we embarked on our European qualifying campaign.

"This game is ideal preparation for our first qualifier against Serbia in Belgrade a few days later. The Oman game also gives us the chance to play in front of Ireland supporters who enhanced their own reputation in France. We are looking forward to both games."

Ireland squad: Darren Randolph (West Ham), Keiren Westwood (Sheffield Wednesday), David Forde (Portsmouth), Seamus Coleman (Everton), Cyrus Christie, Richard Keogh, Alex Pearce (all Derby), Paul McShane (Reading), John O'Shea (Sunderland), Ciaran Clark (Newcastle), Marc Wilson (Bournemouth), Stephen Ward (Burnley), James McClean (West Brom), Glenn Whelan (Stoke), Aiden McGeady, James McCarthy (both Everton), Jeff Hendrick (Derby), Stephen Quinn (Reading), David Meyler (Hull), Harry Arter, Eunan O'Kane (both Bournemouth), Callum O'Dowda (Bristol City), Robbie Brady, Wes Hoolahan (both Norwich), Robbie Keane (LA Galaxy), Shane Long (Southampton), Daryl Murphy (Ipswich), Jonathan Walters (Stoke).

Will Grigg will miss Northern Ireland's World Cup qualifier against the Czech Republic due to personal reasons, while Burton's Tom Flanagan and Dundee loanee Michael Duffy have won their first senior call-ups.

It is understood Wigan striker Grigg's partner is due to give birth and he will therefore remain at home while Michael O'Neill's squad head to Prague for the first game of the 2018 World Cup qualification campaign.

Burton defender Flanagan and midfielder Duffy, whose parent club is Celtic, will link up with O'Neill's squad for the first time having played for the Under-21s in the past while striker Liam Boyce, who narrowly missed out on a place in the 23-man squad for Euro 2016, is recalled.

From the 23 players O'Neill took to the country's maiden European Championship finals in France, only Chris Baird has announced his international retirement, though there is no place in this squad for either 38-year-old Roy Carroll or 36-year-old Aaron Hughes.

Uncapped Hartlepool goalkeeper Trevor Carson has been brought in as one of Michael McGovern's back-ups instead of Linfield's Carroll, while Hughes is considered to be behind fitness-wise having moved to the Indian Super League, which does not begin until December.

Gareth McAuley, whose own goal ended Northern Ireland's time in France, will continue his international career at the age of 36.

As well as Boyce's return, there is also a recall for Peterborough full-back Michael Smith, another from the group of five that was trimmed from the original 28-man group O'Neill had named in his extended Euros squad.

O'Neill revealed Grigg requested to be left out from international commitments, with the team due to go to Austria for a training camp next week before heading on to Prague.

"Will asked to be excused," O'Neill said on Sky Sports News HQ.

"His partner is due (to have) a child and, given that the game is away as well, it's slightly more difficult if he was needed.

"He just felt in this situation that he would be better to stay at home and he asked not to be selected for this squad."

The transfer window will shut before Northern Ireland take to the field against the Czech Republic, and defender Jonny Evans may have switched clubs before he next pulls on the green jersey.

Arsenal are thought to be keen on the 28-year-old West Brom player, who enhanced his reputation during an impressive Euros campaign.

"Jonny was outstanding in France," O'Neill added. "He can switch in and out of systems. He's a top-level player and could play in a top-four Premier League club. The interest from Arsenal doesn't surprise me."

Northern Ireland squad for the World Cup qualifier against the Czech Republic in Prague on September 4:

McGovern (Norwich), Mannus (St Johnstone), Carson (Hartlepool), McAuley (West Brom), J Evans (West Brom), Cathcart (Watford), McLaughlin (Fleetwood), Hodson (Rangers), Smith (Peterborough), Flanagan (Burton), Davis (Southampton), McGinn (Aberdeen), Norwood (Brighton), C Evans (Blackburn), Ward (Nottingham Forest), Ferguson (Millwall), Dallas (Leeds), McNair (Sunderland), Duffy (Dundee), Lafferty (Norwich), Magennis (Charlton), Washington (QPR), Boyce (Ross County).