Marc Warren and Paul Dunne finished their first rounds with a flourish to lead the Open de Espana, while Jon Rahm and amateur Victor Pastor are just one shot off the pace in their homeland.
Warren, without a victory on the European Tour since 2014, birdied five of the last seven holes to start with a six-under 66 at Centro Nacional de Golf on Thursday.
The 37-year-old has failed to finish in the top 50 this year, but made just one bogey at the fourth and raised his game on the back nine to take over at the top of the leaderboard in Madrid.
Dunne matched Warren's opening round when he went out later in the day, the Irishman conjuring up an eagle at 18 after making three of his five birdies on the back nine.
Rahm arrived on home soil buoyed by a fourth-place finish in the Masters last weekend - his best showing in a major - and put himself firmly in contention to claim a first professional title in Spain.
The world number four hit the turn in 34 after starting on the back nine, an eagle three at 18 putting a spring in his step following his solitary dropped shot at the previous hole.
Rahm - who spent two years practicing on the course earlier in his career - made further gains at the third, fifth and seventh in a strong start to his challenge.
Pastor, 113th in the Amateur Golf Ranking, started with an eagle and came up with five birdies before a bogey at the last cost him a share of the lead.
Jason Norris, Jonathan Thomson, Julien Guerrier, Erik van Rooyen and Matthias Schwab are also just a solitary shot behind the leading duo on five under along with Alexander Bjork, Henric Sturehed, Callum Shinkwin and Aaron Rai.
Andrew Johnston, 2016 winner and defending champion as the tournament was not on the European Tour schedule last year, is among nine players a further stroke back.
16. Juli 2018
|Stones will watch re-runs of England´s World Cup matches|
|Ferdinand challenges Mourinho to unleash Pogba at United|
|Mbappe: I´m staying at PSG|
|Former NHL goalie Ray Emery found dead|
|Pirates secure five-game sweep of Brewers with walk-off win|
|WATCH: LeBron receives standing ovation at Lakers´ summer league game|
|Tony Romo wins celebrity-filled American Century Championship|
|McGregor praises Putin after attending World Cup final|
|Open-bound Kim claims maiden title with eight-shot triumph|
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|World Cup winner Rami retires from international football|
15. Juli 2018
|Wimbledon champion Djokovic did not expect grand slam glory so soon|
|Ibrahimovic praises Pogba after World Cup final display|
|Wimbledon diary: Avengers too late for an Infinity War as Djokovic triumphs|
|Deschamp-agne – France´s 2018 vintage interrupt news conference to drench coach|
|I may have to dust my boots off! - Pele threatened by Mbappe exploits|
|WATCH: Mendy and Pogba dab with president Macron after World Cup win|
|Woods embracing ´different´ Carnoustie challenge ahead of Open return|
|Argentina dismiss Sampaoli after chaotic World Cup|
|France celebrates World Cup triumph|
|Djokovic made ´improvised Wimbledon trophies´ as a boy|
|Stone goes agonisingly close to 59 as Pepperell & Dantorp also make Open|
|Outcast Benzema delights in France win|
|Final a triumph in itself given Croatia´s off-field turmoil|
|Anderson laments Wimbledon final nerves|
|Deschamps joins elite club, Mbappe second to Pele - the best stats from the World Cup final|
|Belgium´s Courtois wins World Cup Golden Glove|
|Collarbone fracture confirmed for ´devastated´ Porte|
|World Cup final player ratings: Griezmann, Mbappe inspire France as Croatia fall short|
|World Cup winner Giroud ends tournament without shot on target|
|Modric wins World Cup Golden Ball|
|Mbappe wins World Cup Young Player award|
|Deschamps redeemed as France win World Cup final for the ages|
|France 4 Croatia 2: Twitter Report|
|Tomlin optimistic over Bell contract|
|Kane wins World Cup Golden Boot|
|Ajax keen on Blind deal - Van der Sar|
|France 4 Croatia 2: Pogba and Mbappe seal thrilling World Cup triumph|
|Anderson would have played another 21 hours to reach Wimbledon final|
|Djokovic delighted to crown ´comeback´ with Wimbledon glory|
|World Cup final interrupted by pitch invaders - Pussy Riot claim responsibility|
|Djokovic´s grass-court U-turn pays ultimate dividends with Wimbledon title|
|Mandzukic makes World Cup history with early own goal|
|Dominant Djokovic beats Anderson to regain Wimbledon title|
|Everybody said I´m done - Degenkolb revels in first Tour victory|
|´Big party´ for Marquez after Sachsenring success|
|Hazard enjoys Belgium´s welcome home|
|Ex-AC Milan president Berlusconi conflicted over Ronaldo to Juventus|
|Spain did not contact Martinez over head coach vacancy|
|Maybe the VAR was watching The Simpsons! - RSL coach Petke slams MLS officials|
|Cubs´ Darvish hopes to return by next weekend|
|France and Croatia name unchanged sides for World Cup final|
|Marquez maintains Sachsenring dominance|
|Courtois claims World Cup has boosted his value|
|Buffon beaten on difficult PSG debut|
|Vince called up for Headingley decider|
|Farah inspires Tigers win over Dragons, Warriors and Roosters triumph|
|Crash forces Porte out of Tour for second year running|
|Ronaldo considered Napoli move, says De Laurentiis|
|Mafi arrested for allegedly assaulting Rebels team-mate|
|Everybody is welcome - Croatia pitch for neutral support in World Cup final|
|West Ham seal club-record swoop for Felipe Anderson|
|Rooney applauds England for capturing fans´ imagination|
|Krajicek urges Anderson to go for broke in Wimbledon final|
|Wimbledon 2018: Djokovic v Anderson in Opta numbers|
|Kohli defends Dhoni after Lord´s boos|
|Wimbledon finalist Djokovic can win the next six majors, claims Krajicek|
|We´re ´blessed´ to watch Mbappe, says Kaka|
|Bogaerts hits walk-off grand slam to deliver Red Sox win over Blue Jays|
|Cardinals dismiss Matheny, name Shildt interim manager|