Ballesteros, troubled by tendinitis in his left wrist, was left on five over, 16 shots behind the leader, his Spanish compatriot Diego Borrego, and failed to qualify for weekend play for the fourth time in six tournaments this year.
"I will have to rest my wrist for at least the next three days so maybe it is an advantage to miss the cut. It hurts when I grip or turn the club," said Ballesteros, whose next appointment with a golf course is at the Spanish Open in two weeks' time.
Howley was in line to challenge Bernhard Langer's El Saler course record of 62 in 1984 when he birdied seven of the first 10 holes. "I forgot about making the cut then and decided to chase Langer's record," said Howley, a former assistant from Milltown, near Dublin.
A six-iron to two feet at the 14th was his only further advance, but the 26-year-old was happy to have moved from four over to four under. "I had been playing well, but not scoring well. I had a good start and that gave me a lot of confidence," he said. A 30-foot putt at the second was followed by birdies at the par-five third and fifth before he picked up four in a row from the seventh.
Peter Baker rued a disappointing finish that saw him drop shots at the last two holes - where he found the green-side bunkers - to leave him four behind Borrego, and one adrift of the pair in second place, Wayne Riley and Tony Johnstone.
Borrego, 24, enjoying the early morning calm on the seaside course, added a 67 to his first day 66. Though he was "unworried" by leading at this stage for the first time, he confessed: "I did not look at the leaderboards because I normally get scared.''
TURESPANA MASTERS (El Saler Golf Club, Valencia): Leading second-round scores (GB or Irl unless stated, * denotes amateur): 133 D Borrego (Sp) 66 67. 136 W Riley (Aus) 69 67, T Johnstone (Zim) 67 69. 137 G Turner (NZ) 69 68; R McFarlane 66 71; P Baker 67 70. 138 A Coltart 71 67. 139 I Pyman 69 70; D Howell 71 68; F Cea (Sp) 70 69; R Burns 68 71; F Tarnaud (Fr) 66 73. 140 A Sherborne 68 72; C Suneson (Sp) 69 71; M Gates 71 69; M Litton 71 69; P Haugsrud (Nor) 70 70; R Karlsson (Swe) 71 69; J Pinero (Sp) 71 69; F Howley 76 64; I Garrido (Sp) 69 71; N Briggs 67 73; F Lindgren (Swe) 72 68. 141 S Bottomley 71 70; J Coceres (Arg) 72 69; O Karlsson (Swe) 68 73; S Torrance 73 68; G Nicklaus (US) 72 69; J Haeggman (Swe) 71 70. 142 D Feherty 70 72; F Valera (Sp) 72 70; G Emerson 73 69; R Chapman 69 73; D Smyth 71 71; J Lomas 71 71; M McLean 72 70. Selected: 149 S Ballesteros (Sp) 76 73.Reuse content