He wasn't a big name draftee, but the immediate impact of Gold Coast half-back Sean Lemmens goes much deeper than just kicks and handballs in his first five games.

Drafted from Port Adelaide, the 19-year-old was taken at pick No. 27 in last year's NAB AFL Draft, and was expected to take time to fit into the SUNS’ line-up with his small frame.

Lemmens tipped the scales at just 66kg, but defensive coach Dean Solomon said there was so much to like about his game from the moment he watched him in last year's Under-18 Championships.

The SUNS made it public at the end of last season they wanted running half-backs to round out their list.  They looked at out-of-favour Magpie Heath Shaw, but passed, and went to the draft instead.

After landing the classy Kade Kolodjashnij at pick No.5, they doubled up with Lemmens later in the draft.

The energetic but quietly spoken South Australian made an immediate impression on the Gold Coast and has not looked back since debuting in round one against Richmond.

"What originally jumped out was his ability to read the play and cut the angles, knowing he had his own opponent covered, but was able to come across and assist another teammate," Solomon said.

"He looked to be a bit above the level at under-18s.

"He has an appetite to be in the contest and you love that in your defenders."

Lemmens has impressed mainly with his defensive work on small forwards, and showed an ability to take an intercept mark under pressure against Melbourne last Sunday.

He is exceptionally quick and agile, and Solomon says the impact of his 13 disposals a game will improve over time.  But Lemmens' rapid impact has meant so much more for Gold Coast.

When they struggled to unearth a rebounding defender last season, former number one pick David Swallow was moved from the midfield.

Swallow was more than adequate in defence – exceptional on occasions – but it wasn't the SUNS' preferred option.

Now back to the middle of the ground, Swallow has flourished in 2014.

"We did educate Dave a bit last year about playing half-back and getting that offence-defence side of his game," Solomon said.

"With Sean and Kade in our side, Dave's probably been our second best player so far this year (behind Gary Ablett).

"The flow-on effect is we're not taking good on-ballers and moving them to half-back, we're leaving our good on-ballers on the ball."

Guy McKenna has always been an advocate of picking players in form, regardless of age, and Lemmens is a prime example.

The SUNS now have genuine competition for places, which has brought the best out of former Docker Greg Broughton.

Broughton came to the club at the start of last season to fill in the half-back role, but his form was patchy, and he was dropped on more than one occasion.

With more competition for places, Broughton has lifted – highlighted by 25 touches, nine marks and a match-sealing goal against Melbourne last start – and McKenna has responded by finding a regular place for him.

"Greg had his review at the end of last year and it was made very clear to him where he sits and that these young guys are coming," Solomon said.

"To Greg's credit he had a terrific pre-season and has worked on a lot of his game. He's been in the system a long time but he's continued to work harder than he has in the past and has said "you're not going past me yet boys".

So while 12.8 disposals to a skinny half-back with just five games to his name doesn't look much, scratch the surface and you can see the impact Sean Lemmens has had.

"We're grateful to have him at our footy club," Solomon said. "But Sean knows, and we know as a coaching group, he still has a lot of work to do on his game. He's just one or two bad games from being out of the team."