Damien Duff believes the Republic of Ireland's chances of qualifying for Euro 2016 are "slim" and that the World Cup 2018 qualifying draw was not as kind to Martin O'Neill's side as many observers believe.
Ireland are fourth in their Euro qualifying group on nine points, five behind leaders Poland, with Scotland second on 11 points. Germany occupy third spot on 10 points.
They face Gibraltar and Georgia in September before crunch ties with Germany and Poland in October.
"I think it'll be difficult," the 101-cap international told RTÉ Sport. "Chances are slim to be brutally honest but we'll see how we go. Six points next month would put us back in it, we'll see."
The Shamrock Rovers new recruit also warned that Ireland's World Cup 2018 qualifying opponents Wales, Austria, Serbia, Moldova and Georgia will pose a stern test.
"People say we've a nice draw for the World Cup but I'm not quite sure about that. I still think it's very tricky so tough times ahead."
Duff was speaking ahead of his anticipated debut for Rovers against Cork City on Monday night (Live on RTÉ 2, 7.05pm)
"I've only been back training three days, and that's three days in seven months, but I'm feeling good and I might nick 30 seconds, a minute or five," he said.
"It's up to the manager. I feel okay training but playing a senior league game is a totally different kettle of fish so we'll see how we go.
"I missed the latter half of the season there [in Australia with Melbourne City]. I had a bad injury and an operation.
"I'm back training now, after seven months. I've been down this route before but I have to show my hunger and desire to get back on the pitch, which always helps.
"It's driven me on. I wanted to come back here and sign for Shamrock Rovers, the biggest club in Ireland, so it was a no-brainer."
Duff said that he has been impressed by the standard in the League of Ireland and that Rovers were not completely out of title contention, despite trailing leaders Dundalk by 12 points, albeit with a game in hand.
"I've been very impressed," he said. "There are some lovely players out there. I know it's not going to be easy for me and I'll have to be at the top of my game to deliver on the pitch. I'm excited about it.
"I know it's a tough league, and it's a young league, so I know it's not going to be easy but I've worked hard to get back so hopefully in another week or two I might be ready to start a game.
"I wouldn't rule out the league. If we go on a nice run and people drop points, let's see what happens.
The 36-year-old firmly ruled out any thoughts of a return to international duty, referencing Shay Given's return and recent announcement that he would hang up his boots once more at the end of the Euro 2016 qualifying campaign.
"No chance," said Duff. "I thought Shay [Given] was crazy enough coming back out and then I read yesterday he was retiring again. I'll leave him at it."
