DEL MAR, Calif. &ndash; The $300,000 Del Mar Oaks on Aug. 21 is likely to have a large field, and that works against trainer Mark Glatt&rsquo;s hopes for It Tiz.\r\nThe field for the Grade 1 Oaks is limited to 10 starters, determined by graded or group stakes winners, or fillies who have placed in such races. It Tiz won the minor Le Cle Stakes at Hollywood Park last month but has had no success in reaching the first three in graded stakes in her career.\r\nWith graded or group stakes winners such as Berg Bahn, City to City, Crisp, Distinctive, Evening Jewel, Harmonious, Perfect Shirl, and Switch, and the graded stakes-placed runners Antares World and Weekend Magic on the list of probable starters, It Tiz could be left out. Berg Bahn and Distinctive won group stakes in Europe.\r\nIt Tiz, who races for Allen and Susan Branch, was sixth, beaten 1 3/4 lengths by Evening Jewel in the Grade 2 San Clemente Handicap on July 25, her first start since winning the one-mile Le Cle Stakes.\r\n&ldquo;I&rsquo;m a stakes winner,&rdquo; Glatt said of It Tiz. &ldquo;She was fourth in the Del Mar Debutante [last year], and I&rsquo;m on the outside.&rdquo;\r\nGlatt will spend this week hoping that a spot in the Del Mar Oaks becomes available for It Tiz, who has won 4 of 9 starts and $194,145. He wants to run in the Del Mar Oaks because of the race distance of 1 1/8 miles on turf and to use the race as a prep for the $400,000 Queen Elizabeth II Challenge Cup at Keeneland on Oct. 16.\r\nBecause the Keeneland race is an invitational, It Tiz needs a strong performance in the Del Mar Oaks to merit attention. As a backup, Glatt is considering sending It Tiz to Arlington Park for the $100,000 Pucker Up Stakes on Sept. 6, a Grade 3 race over 1 1/8 miles on turf.\r\nFriday&rsquo;s $75,000 Sandy Blue Stakes over a mile on turf for 3-year-olds fillies is not prestigious enough for It Tiz, he said.\r\n&ldquo;If she runs in the Sandy Blue, I don&rsquo;t know if that will get her into the race at Keeneland,&rdquo; he said.\r\nThe Del Mar Oaks will have a strong field. Evening Jewel, who has won three graded stakes this year and lost the Kentucky Oaks by a nose, and Harmonious, who won the Grade 1 American Oaks at Hollywood Park last month in her stakes debut, are the leading contenders.\r\nGonzalez out after concussion\r\nApprentice jockey Alex Gonzalez will be sidelined until at least Aug. 25 after suffering a concussion when unseated during a race Wednesday, according to his agent, Vince De Gregory.\r\nGonzalez, 18, was hospitalized overnight Wednesday and was advised by doctors to take a week off from riding, De Gregory said. Gonzalez, who has one win in 24 mounts at this meeting, complained of headaches after he was unseated when his mount clipped heels with a rival in the stretch of Wednesday&rsquo;s fifth race.\r\nGonzalez will need doctor&rsquo;s approval to resume riding.\r\n&ldquo;The doctor said to wait a week,&rdquo; De Gregory said. &ldquo;There is no sense in rushing him.&rdquo;\r\nValenzuela dealing with sore knee\r\nJockey Patrick Valenzuela missed his last four rides on Thursday&rsquo;s program because of a sore knee, but was scheduled to ride this weekend, according to agent Tom Knust.\r\nValenzuela told Knust that he strained his knee when pulling up Big Wig after the fourth race Thursday. Big Wig was vanned off and was reported by track stewards to be unsound.\r\nThrough Thursday, Valenzuela was tied for fifth in the standings with nine wins, trailing leader Joel Rosario, who has 26 wins.\r\nValenzuela began riding at this meeting on July 28, a week after opening day. Troubled by substance-abuse problems that have led to multiple suspensions in his career, the 47-year-old Valenzuela was granted a conditional license by the California Horse Racing Board on July 22, allowing him to resume riding in California for the first time since late 2007, subject to drug testing. Valenzuela rode in Louisiana and New Mexico in recent years.\r\nHis success in recent weeks has exceeded Knust&rsquo;s hopes.\r\n&ldquo;This is more than I expected,&rdquo; he said. &ldquo;I think we have some live horses this weekend. We&rsquo;ve got good business for the next&rdquo; few weeks.\r\nValenzuela won his first stakes of the meeting aboard J P&rsquo;s Gusto in the Best Pal Stakes last Sunday. This Sunday, he rides Sprint Style in the John Mabee Stakes.\r\nCost of Freedom set for Green Flash\r\nCost of Freedom, the multiple stakes-winning sprinter, will make his first start on turf in Wednesday&rsquo;s $75,000 Green Flash Handicap over five furlongs.\r\nCost of Freedom finished fifth as the 3-5 favorite in the Grade 1 Bing Crosby Stakes here Aug. 1, essentially losing all chance after stumbling at the start.\r\nTrainer John Sadler solidified plans to run Cost of Freedom in the Green Flash after the 7-year-old gelding worked a half-mile in 47.20 seconds on the surface Thursday morning.