Home favourite Marin Cilic can win a fourth Zagreb Indoors title when the tournament gets under way in Croatia on Monday.
The world number 37 suffered a disappointing Australian Open campaign, bowing out to Gilles Simon in the second round, but will return to his native Croatia eyeing a fourth win in six years at the ATP 250 Series event.
Cilic, a winner in 2009, 2010 and 2013, clinched the title last year with a 6-3 6-1 victory over Jurgen Melzer and will begin his defence against compatriot Mate Delic - a 20-year-old wildcard.
The number five seed has the chance to overtake coach and former world number two Goran Ivanisevic in terms of ATP titles won in Croatia with victory in Zagreb, after Ivanisevic picked up four winner's medals in his homeland.
"Goran is an excellent coach. He passes everything he knows on to me. We have had super preparations and my inner feeling is that I play better than before. All I have to do now is demonstrate this in the matches," Cilic told the tournament's official website.
"(Ivanisevic's record) will not be an additional motive for me. Naturally, it would be nice to raise the winner's trophy again. But, our main goal in this season is to achieve the best possible results at Grand Slam tournaments and at ATP Masters Series."
World number 12 Tommy Haas will make his debut in Zagreb as top seed, having recovered from the shoulder injury that forced him to retire during his first-round clash with Guillermo Garcia-Lopez at the Australian Open.
Mikhail Youzhny and Ivan Dodig, both former winners of the competition, are seeded second and fourth respectively, although two of the world's top 20 have been ruled out due to injury.
Croatian Milos Raonic, number 11 in the world, misses out with an ankle complaint, while Grigor Dimitrov cited his need for rest and recovery as his reason for withdrawal, having suffered a recurring leg injury.
Dimitrov, who reached his first grand slam quarter-final in Melbourne, explained his decision, as he said: "I am very disappointed that I won't be able to compete at PBZ Zagreb Indoors this year.
"The accumulations of matches in Australia and a leg injury makes necessary to give my body a rest to recover."
|Premier League Preview: Norwich City v Liverpool|
|Maxwell inspires Kings XI victory|
|Moyes outlines transfer plans|
|Anigo confident of Bielsa arrival|
|Pellegrini ´absolutely sure´ of Liverpool, Chelsea slip-ups|
|Solskjaer slams ´unfounded´ Gunnarsson reports|
|A-League: Melbourne Victory 2 Sydney 1|
|Seedorf calls for focus|
|Tombides loses cancer battle|
|Holland: FA could have helped Chelsea more|
|Mattiacci not giving up in pursuit of Mercedes|
|Premier League Preview: Everton v Manchester United|
|Ferrer sends Nadal crashing out in Monte Carlo|
|Costa backs Atletico in title run-in|
|Terry closing in on new Chelsea deal|
|Westwood extends Malaysian Open lead|
|Premier League Preview: Hull City v Arsenal|
|English football should support Chelsea - Bruce|
|Guardiola confident in Bayern after mini-slump|
|Van Basten agrees deal at AZ|
|Cardiff confidence high ahead of Stoke clash|
|Hamilton not content despite promising practice|
|Success of Pulis good for British managers - Allardyce|
|Hernanes: Inter will challenge for titles|
|Pulis slams ´disappointing´ Cardiff conduct|
|Hannover safety not assured, claims Korkut|
|Conte focused on Juve title quest|
|Suspension issue no bother for Hamilton|
|I want a hostile Goodison for Moyes return - Martinez|
|Trott to take a break after relapse|
|Umtiti confident of Coupe de la Ligue upset|
|Van Dijk plays down Premier League links|
|I know who is trying to unsettle us - Monk|
|Bale targets Bayern after Copa success|
|Pardew: Remy and Newcastle are a good fit|
|Costa Rica Primera Division Wrap: Alajuelense close in|
|Blues outlast Blackhawks in series opener|
|Klinsmann: US mentally equipped for World Cup|
|Five-star Yankees overpower Rays|
|Alonso fastest in China|
|Hodgson wary of Pirlo threat|
|Prib: Hannover not safe yet|
|Tevez hails ´top-level´ Conte|
|Argentina Primera Division Wrap: Colon edge closer to leaders|
|Copa Libertadores: The Strongest 2 Defensor Sporting 0|
|Spain easier to represent than Brazil, says Luis|
|Robson out of French Open, Wimbledon|
|Pochettino expects Shaw stay|
|Cannavaro keen to coach in Italy|
|Copa do Brasil Wrap: Goias stunned|
|Kuchar makes bright start at RBC Heritage|
|Hantuchova eyes consistent form in Marrakech|
|Simeone focused on Elche|
|Howard extends Everton deal|
|Bundesliga: Eintracht Frankfurt 2 Hannover 3|
|Spanish rivals on verge of semi-finals|
|Primeira Liga: Vitoria Guimaraes 2 Arouca 3|
|Kiltschko expects exciting Leapai fight|
|Cannavaro has faith in strong Italy team|
|Premier League Preview: Tottenham v Fulham|
|Rosberg will discuss Bahrain duel with Hamilton|
|Yuvraj in the runs on Bangalore debut|
|O´Sullivan aims for three in a row at the Crucible|
|Premier League Preview: Newcastle United v Swansea City|
|Destro suspension appeal rejected|
|Neymar, Alba out for up to a month|
|Higuain set to miss Udinese clash|
|Bundesliga Preview: Eintracht Braunschweig v Bayern Munich|
|Hughes confirms Olic interest|
|Djokovic eases through, Nadal reaches new milestone|