[5] Serhan first achieved notable press coverage with his first round play at the 1975 New South Wales Open.

[9] However, he again "collapsed" with a chance to win, making a triple bogey on the par-3 8th hole and shooting a final round 77 (+6).

[18] In September 1979, he played well at the New South Wales PGA Championship, maintaining joint second place after the first two rounds.

[13] The following week, he finally won on the PGA Tour of Australia at the New South Wales Open.

[13] Aided by Serhan's bogeys on the 11th and 13th holes, however, Scotland's Sam Torrance got within two shots of the lead.

[24][3] This excellent play helped Serhan qualify for Australia's 1980 World Cup team.

[25] The 1980 World Cup was played in Bogotá, Colombia and Serhan's teammate was Bob Shaw.

Unfortunately, Shaw became ill and had to withdraw from the tournament, resulting in that the Australia team was out of the competition.

However, Serhan continued to play and completed the individual competition, finishing with 303 strokes, tied 32nd among 88 players.

At the first round of the Illawarra Open, he shot a 69 (−3) to tie Bill Dunk and Ian Stanley for the lead.

[34] A year later, in December 1984, he shot a third round 70 (−2) at the Queensland PGA Championship to put himself in the top-10, within striking distance of the leaders.

[36] The following year he finished in 6th place at the 1985 Australian Open, tied with Tom Watson and Mike Harwood.

Serhan shot a third round 67 (−6), tying the best of the day among the 66 competitors, putting himself in contention for the tournament.

[38] During the final round Serhan birdied four holes on the front nine and after leader Wayne Riley bogeyed the 9th the two were tied.

After Serhan bogeyed the 12th, his competitor holed a 13-metre eagle putt on the 13th to suddenly create a three shot advantage.

In 1986, in need of a stable job to support his young family, he spent most of the year working at a driving range in Sydney.

In October 1987, he shot a 68 (−5) in the first round of the Australian PGA Championship, placing him one behind Northern Ireland's Ronan Rafferty.

[43] A month later, he tied the course record with a 69 (−3) in the third round at the National Panasonic WA Open to put himself in contention.

[45][46] Later in the year, in November, he again played well during the first round of the Australian PGA, recording seven birdies, shooting 68 (−4) to place himself only two back to Brett Ogle.

In the beginning of the year, in January, he finished in a tie for 5th at the Daikyo Palm Meadows Cup with Japan's Isao Aoki and America's Jeff Maggert.

In the star-studded event, he only finished behind champion Curtis Strange, runner-up Raymond Floyd, and fellow Australians Terry Price and Peter Fowler.

He defeated big names like Jumbo Ozaki, Greg Norman, and Mark O'Meara.

He opened the PGA Tour of Australasia year with three straight missed cuts and did not record a top-25 until March.

Serhan played excellently at the six round Toshiba pro-am golf series in April 1991.

[62] Serhan then fired a fourth round 68 (−5) to build an eight shot lead over American Wayne Case.

His wife was also an excellent golfer and won the 1975 Australian Foursome Championship, an amateur tournament.