Celtic have agreed a deal for 21-year-old centre-back Jozo Simunovic although the fee is officially unknown it is believed to be in the region of £5 million.

The Croatian is highly rated in his home nation and is likely to be a direct replacement for the outgoing Virgil Van Dijk.

There were reports that a bid of £4 million was rejected by the Croatian side several weeks ago and it looks like Celtic have stepped up their pursuit of Simunovic according to Sky Sports Scotland on Twitter.

SKY SOURCES: @celticfc agree fee with @gnkdinamo for defender Jozo Simunovic. Player will travel to Glasgow for medical & to discuss terms — Sky Sports Scotland (@ScotlandSky) August 31, 2015

He will now travel to Glasgow to discuss personal terms and complete a medical.

Simunovic has come through the ranks at Dinamo Zagreb having joined aged 12 and made his first senior start as a 19-year-old in the Europa league against Chornomorets Odesa.

He has been a regular in the Zagreb defence over the last two seasons making 52 appearances and scoring three goals. The Croatian also picked up eight Under-21 caps for the national side and has been capped at every level since Under-16, with a senior call-up probably not too far away.

Celtic have seen him play up close before during last year’s Europa League group stages when Celtic lost 4-3 in Zagreb with Jozo coming on after 11 minutes due to an injury to his teammate.

Tyler Blackett joined the Hoops on a season-long loan deal at the weekend and this latest signing would be Deila’s seventh of the summer.