Disappointed Estonia manager Martin Reim believes Northern Ireland only have a chance of upsetting European heavyweights Germany and the Netherlands in Group C if they are able to replicate the form they showed in defeating his side 2-0 in Belfast.
eim felt Northern Ireland were fortunate to leave the A Le Coq Arena on Saturday with all three points after skipper Konstantin Vassiljev had given Estonia the lead, they'd a debatable goal ruled out for an infringement on keeper Bailey Peacock-Farrell and Vassiljev struck the bar with a thunderous shot.
Two late goals from second-half substitutes Conor Washington and Josh Magennis kept Michael O'Neill's men top of Group C on nine points with the games against Germany and Holland coming in September, October and November.
Reim, Estonia's most capped player with 157 appearances, was impressed by Northern Ireland at Windsor in March, but feels they will have to greatly improve on their performance in Tallinn.
"It depends what condition they are in come September," replied Reim when asked how far Northern Ireland could go.
"How they played in March, they can get points from Germany and Netherlands but today it was more difficult. Northern Ireland can give problems."
Reim thought Jordan Jones, who came on for Michael Smith, made a big difference and said: "Northern Ireland made good changes and the left midfielder (Jones) was good and quick with his feet, we had a problem."
Reim's players protested that Magennis was offside when Washington's shot struck him for Northern Ireland's equaliser, but the Estonian boss said: "I don't know (if he was offside). Maybe it was a deflection, offside or not, there is nothing to do."