FREMANTLE forward Josh Treacy has spearheaded a professional 51-point win against Richmond on Saturday night, kicking a career-best bag of five goals at Optus Stadium as the Dockers closed the gap on the top two. 

Treacy was outstanding and took his season tally to 35, setting up the match-winning break with four first-half goals as the Dockers celebrated Justin Longmuir's 100th game as senior coach with a 16.9 (105) to 7.12 (54) win. 

DOCKERS v TIGERS Full match coverage and stats

The win came at a cost as No.1 ruckman Sean Darcy entered concussion protocols and young key defender Josh Draper copped a corked leg that saw him eventually pulled from the game after playing through the issue. 

The Tigers, who moved to the bottom of the ladder on Saturday and lost their third straight game by 48 points or more, fought hard for long periods but could not counter the gulf in talent as the Dockers rattled on nine second-half goals.  

As well as Treacy, vice-captain Andrew Brayshaw was superb in a prominent midfield role, stepping up to finish with a game-high 35 disposals, six clearances and a goal. 

The midfield was out-pointed in clearances by the hard-working Tigers but controlled the transition game and rotated through the forward line as Hayden Young booted two goals to complement his 24 disposals in another fine performance. 

Luke Jackson stepped up in the ruck and showcased his exciting ground-level attributes through the second half, but was up against powerful big man Toby Nankervis who led from the front with 26 disposals, 36 hitouts and 11 clearances for the Tigers.   

Shai Bolton booted four goals for the visitors and stepped up as he so often does in his home state. 

Treacy looked like a man on a mission to open Saturday night's clash, leading well up the ground to take important marks, laying big tackles, and drawing the ball inside 50 to kick three of the Dockers' first four goals. 

He forced the Tigers to take second-gamer Jacob Blight off him at quarter-time and hand the job to Ben Miller as the visitors' early 12-point lead was quickly erased and the Dockers took control of the game in the midfield. 

Defender Heath Chapman provided an early highlight when he took the rare chance to show his goalkicking credentials in attack, converting a set shot from the boundary line from just inside 50 as the Dockers headed to the first break with a 15-point lead. 

The second quarter was controlled by Richmond as it won the clearances (14-7) and broke even in forward entries (14-14). But it lacked the forward-half polish to take advantage, kicking five straight behinds before Bolton got free out the back to kick his second. 

The Dockers, meanwhile, overcame what Longmuir said was one of their worst quarters of the season to still kick three goals and build their lead to 24 points, with Brayshaw snapping accurately with three seconds left in the half. 

The third quarter highlighted why these teams are at different ends of the ladder. While the Tigers continued to fight hard, they were shown up by the Dockers' talent as they piled on five unanswered goals to build a game-high 47-point lead. 

Jackson took over in the ruck and shone, taking the ball out of a centre bounce and spinning before taking off at ground level and delivering inside 50 after a bounce to set up Sam Switkowski for a goal. 

Substitute Michael Walters also came into the game for Darcy and kicked two goals in his return from a hamstring injury as the Dockers adjusted to a smaller forward line structure. 

In defence, Draper looked limited after being hobbled by a knock to the groin early in the game. He played on until being taken out of the game early in the fourth term when the result was beyond doubt.

Graham turns hand to tagging
Richmond turned to Jack Graham to play a tagging role on Saturday night, with the dual premiership Tiger sent to Brownlow Medal contender Caleb Serong at the first bounce. While Graham couldn't stop Serong from getting the ball, he was able to limit his effectiveness as the Dockers continued rotating their star onballers forward. Serong had 16 disposals and four clearances in the first half, but he was limited to 50 per cent efficiency and just two score involvements. He finished with 27 touches, fighting hard through the attention. 

Another Darcy setback 
The Dockers will be without No.1 ruckman Sean Darcy in a big game against Hawthorn next Saturday in Tasmania after he entered concussion protocols. The Dockers confirmed Darcy had suffered concussion after he stumbled at a ruck contest and copped a knee to the head. It's the big man's third setback this season after a knee injury ruled him out for the early rounds before a mid-season calf issue. Luke Jackson will likely carry the No.1 ruck mantle again, while tall forward Pat Voss booted six goals in the WAFL on Saturday and would allow the Dockers to maintain their preferred structure in attack.   

Tigers flip the stoppage script 
The Dockers are the No.1 clearance differential team in the AFL and the Tigers are bottom four. But the performances of Nankervis (11 clearances), Tim Taranto (four) and Jacob Hopper (six), and a strategy to get extra numbers to stoppages meant the Tigers won the clearances 37-24 after quarter-time and 43-37 overall. It didn't convert to field position, however, with a lack of outside polish costing them. It also showed that the Dockers can still score in other ways when one of their biggest strengths is stripped away.  

FREMANTLE   4.3   7.5   13.6   16.9 (105)
RICHMOND   2.0   3.5   5.8   7.12 (54)   

GOALS 
Fremantle: Treacy 5, Frederick 2, Walters 2, Young 2, Amiss, Brayshaw, Chapman, O'Meara, Switkowski
Richmond: Bolton 4, Mansell, Nankervis, Taranto 

BEST
Fremantle: Treacy, Brayshaw, Young, Jackson, Ryan, Serong, Johnson  
Richmond: Nankervis, Bolton, Rioli, Hopper, Taranto

INJURIES
Fremantle: Darcy (concussion), Draper (corked leg) 
Richmond: Nil 

SUBSTITUTES
Fremantle: Michael Walters (replaced Sean Darcy at half-time) 
Richmond: Sam Banks (replaced Jacob Blight in the third quarter) 

Crowd: 42,690 at Optus Stadium