Gareth Turnbull runs in San Sebastian on Saturday

Turnbull got boxed on the first lap and found himself near the back of the 17-strong field after two laps.

The Belfast man made a brave effort on the final lap and passed several athletes to move up to eighth.

Algerian Tarek Boukensa was an impressive winner of the Zagreb race in a time of 3:35.77.

Turnbull will hope to get closer to the Olympic qualifying mark of 3:36.20 in San Sebastian on Saturday.

His rivals in San Sebastian will include Spanish stars Reyes Estevez and Jose Redolat.

The Belfast man will then be in action in Stockholm on 7 July.

Turnbull ran 3:40 on two occasions in the US in late May.

"There is a particularly strong field for the race in San Sebastian and hopefully I will be able to take two or three seconds off what I ran in US."

Last week, Turnbull said that it would probably be unrealistic for him to better the Olympic mark in Zagreb and San Sebastian, with the latter his final chance before the Olympic Council of Ireland's qualification deadline of this weekend.

However, he believes that he is on course to achieve the time later in July and if he did that, he would hope that the Irish Olympic body would take another look at his claims.

The final IAAF deadline for Athletes to be selected for Athens in 9 August.