A showdown between Haymaker and Colonel Hill yesterday developed into a showcase for Forry Cow How, who charged past the two favorites to win the $60,000 Star de Naskra Stakes for Maryland-breds at Laurel.

The Haymaker-Colonel Hill confrontation had grown on track and off it. Each had beaten the other once in pursuit of a Maryland-bred juvenile title, and their managers shared few tidings of goodwill. But a battle between the newly turned 3-year-olds never materialized; Colonel Hill dropped from contention after chasing Haymaker six furlongs of the seven furlong race, and Haymaker's lead faded five strides from the wire when Forry Cow How went past, Gala Spinaway pressed to his left flank.

Forry Cow How lasted for a half-length victory over Gala Spinaway, with Haymaker another neck behind in third. Colonel Hill, the 9-5 second choice behind even-money Haymaker, outdistanced One Tuff Oop for last place, which still brought $1,800.

After seeing both Haymaker and Forry Cow How nominated for the Star de Naskra, agent Tom Hauer went to work. Each horse was coming off a win under Marco Castaneda, and Hauer said he knew Castaneda would choose the more established of the two, Haymaker. Hauer petitioned Ron Cartwright, Forry Cow How's trainer, and Joe Rocco got the mount.

While Haymaker had a two-length lead over Colonel Hill well into the far turn, Rocco was whipping Forry Cow How. "I would have sat longer, but it looked like Marco had a lot of horse left," he said.

Rocco said Forry Cow How caught a clump of dirt in his left eye, so he swung out the gray colt into the stretch and witnessed a final furlong of 12 1/5 seconds. Forry Cow How was clocked in 1:25 on a dry track that produced relatively slow times.

He made $36,000 for Buckingham Farm owners Ed and Binnie Houghton, who have been preoccupied with other matters. Their 24-year-old daughter, Jen, suffered a spinal injury in a Dec. 24 riding accident at Fair Hill, but the Houghtons said the fear of paralysis appears lifted.

They named Forry Cow How after "a beautiful sheep farm in New Zealand," and the son of Horatius has two firsts and a second in three starts. He paid $17.60 yesterday as fourth choice out of five. Laurel-Pimlico Up

Although an economic downturn affected racetracks nationwide in 1990, Laurel and Pimlico combined for increases in attendance and handle for the sixth straight year. Over 263 racing days, the tracks averaged $1,657,315 in wagers, a 2.7 percent rise over 1989, and 10,959 fans, a 1.4 percent increase.

For its fall meeting that ended Monday, Laurel's average handle ($1,585,009) was up 2.4 percent and the attendance (10,103) was down .3 percent. Jockey and trainer records will be perpetuated through this spring meet, which ends in mid-March. . . .

Mark Johnston, the leading candidate for Eclipse Award winning apprentice, led Maryland jockeys in victories last year. According to the Maryland Thoroughbred Purse Account, Johnston won 320 races, 15 more than second-place Edgar Prado, and led the circuit with 1,876 mounts. Joe Rocco was third in wins with 191, followed by Mario Pino (188), Mike Luzzi (169), Marco Castaneda (141) and Donnie Miller Jr. (130).

Johnston lost his apprenticeship late in July after he had won 249 races.

The most proficient rider with at least 100 mounts was Kent Desormeaux, who won 22.9 percent of the time (24 of 105).

Predictably, King Leatherbury led trainers and had more than twice as many winners as his closest rival. Leatherbury's total of 154 easily surpassed that of Fran Campitelli (73). Dale Capuano won 71, Howard Wolfendale 61, Carlos Garcia 60 and John Hartsell 57.

Capuano's production was lower largely because he served three suspensions totaling 65 days. Including those winners saddled in his absence by his father, Phil, Capuano had 84 winners. . . .

With his victory Monday, Fire Plug won the Resolution Handicap for the second time in 1990. He also took the sprint last Jan. 1. . . . Jockey Rick Wilson called in sick yesterday.