England's Paul Waring made the biggest move in the early stages of the second round of the Portugal Masters to add to the congestion on a packed leaderboard.
Waring was one of 68 players to break par on Thursday at the Oceânico Victoria Golf Course, carding a four under par 67 that left him two shots off the overnight lead shared by seven players.
And he was soon back among the birdies on Friday morning, picking up shots at the first, fifth, sixth and eighth to improve to eight under par as he went in search of a first European Tour title.
Waring was just one of five players sharing the lead, however, with Chile's Felipe Aguilar, South African Hennie Otto, Austria's Bernd Wiesberger and France's Julien Quesne also eight under.
England's Graeme Storm remained six under after two holes of his second round, while fellow joint overnight leaders David Lynn, Jamie Donaldson, Alvaro Quiros and Simon Thornton were among the later starters.
Ryder Cup hero Martin Kaymer was a shot further back on five under, the former World Number One starting his second round on the back nine and picking up shots on the 12th and 15th.
Kaymer, whose victory over Steve Stricker ensured Europe would retain The Ryder Cup in the 'Miracle at Medinah' last year, had yet to drop a shot after a flawless opening 68.
Waring picked up his fifth birdie of the day on the par five 12th, but that was not good enough to keep him in a share of the lead as the low scoring continued.
Quesne, who won the 70° Open d’Italia Lindt in Turin last month, had followed an eagle on the 12th with three birdies in succession before a bogey on the 16th, but responded with another birdie on the 17th.
That took him to ten under par and alongside Wiesberger, who had covered the back nine in 31, and Otto, who had eagled the 12th for the second day running.
Otto and Waring were playing in the same group and clearly spurring each other on, Otto making birdies on the 17th and 18th to complete a 64 and Waring picking up shots on the 15th, 16th and 18th to go one better.
That left the duo tied for the clubhouse lead on 12 under par, two shots clear of South African Justin Walters who had matched Waring's 63.
Wiesberger remained ten under with four holes to play, but Quesne had dropped three shots in succession to fall back to seven under.
