Goals from Dan Happe, Josh Coulson, James Alabi and Josh Wright secured a third straight victory in League Two, as Embleton led his team to an astonishing away win.
The O’s made two changes to the starting 11, as Marvin Ekpiteta and James Dayton came in for Myles Judd and the suspended Conor Wilkinson.
Following a slow opening ten minutes, the O’s bagged the opening goal with their first clear cut opportunity of the afternoon.
Dale Gorman found Marvin Ekpiteta in a good position in the area, with the latter finding Dan Happe in the middle of the box, who smashed the ball home after his original effort had been well saved by Grimsby ‘keeper James McKeown.
Happe’s goal lifted the mood and the O’s looked confident as they went on to dominate vast spells of the first half, with the Mariners lacking a creative spark whenever they got close to Dean Brill’s goal.
Another opportunity to get the ball in the area was rewarded as Captain Josh Coulson fired his side into a 2-0 lead after 21 minutes.
Wright’s low free-kick into the box caused all kinds of problems for the defence, who failed to clear, and Coulson capitalised finding the net with a first-time effort with his right-foot.
Michael Jolley’s team looked to pull a goal back immediately but were denied by Dean Brill who got down well to cover his near post, as Jake Hessenthaler looked to sneak the ball past the Orient ‘keeper from just inside the area.
Grimsby man Luke Hendrie was the first player to receive a yellow card, but Matt Harrold soon followed him into the book, as Referee Nick Kinseley cautioned the forward for a late tackle on Harry Clifton.
James Dayton was next to receive a yellow card for allegedly wasting time, as he handed the ball to Marvin Ekpiteta to take a throw-in rather than himself. Ekpiteta was originally booked, but the Referee changed his decision, and booked Dayton.
A fiery end to the first phase of play was well managed by Leyton Orient, who ensured they kept a firm hold on the game and took a 2-0 lead into the break.
Grimsby made a much better start to the second half and it wasn’t long before Brill was forced into another save.
Substitute Matt Green volleyed the ball goal-bound, but Brill was alert to the danger and palmed the effort away.
Louis Dennis was introduced shortly before the hour mark, as James Dayton made way for the summer signing, who could have scored moments after coming onto the pitch.
An electric run from James Brophy down the left channel exposed the Grimsby defence, and the Orient man found Dennis in the middle, but the forward couldn’t steer his strike on target.
Craig Clay’s curling effort from the edge of the 18-yard box looked destined for the top corner, but McKeown miraculously kept the ball from going in and tipped it behind for a corner.
The final half hour was tense with both sides attacking in hope of grabbing the next goal. Right-back Luke Hendrie picked out teammate James Hanson with a perfect cross, but the striker’s finish didn’t match the ball, and he headed wide from ten yards.
Another header inside the area was wasted by Grimsby, this time Elliott Whitehouse failed to hit the target with the goal beckoning.
James Alabi and George Marsh were brought on, with Matt Harrold and Dale Gorman coming off, with the two goal lead still intact with 15 minutes remaining.
Coulson was denied a second goal by Ahkeem Rose who cleared the ball off the line after the Orient centre-back volleyed towards the bottom corner.
With ten minutes to go, the victory was wrapped up by substitute James Alabi, who scored a third O’s goal. The striker intercepted possession on the half-way line and had the whole of the opposition half to run into. Alabi covered forty yards before coolly slotting the ball into the bottom corner. A superb goal at a vital time in the game.
The same man was at the centre of attention again, winning his side a penalty as he beat his marker to the ball just inside the area. Midfielder Josh Wright placed the ball on the spot, before firing into the same corner Alabi had found before him, as Orient claimed a four goal lead, four minutes from time.
Grimsby fans poured out of the ground with the tie out of reach, as all 383 Orient supporters bellowed out chants right to the final whistle. An away day to remember, as the game finished 4-0 to Leyton Orient.
ORIENT: Brill, Ekpiteta, Coulson, Happe, Widdowson, Clay, Gorman (Marsh 73’’), Wright, Dayton (Dennis 56’’), Brophy, Harrold (Alabi 68’’)
SUBS: Sargeant, Ogie, Judd, Maguire-Drew
GOALS: Happe 11’’ Coulson 21’’ Alabi 80’’ Wright 86”
BOOKED: Harrold 28’’ Dayton 37’’
GRIMSBY: McKeown, Hendrie, Gibson, Öhman, Waterfall, Hessenthaler, Hanson, Rose, Clifton (Ogbu 46’’), Vernam (Green 46’’), Hewitt (Whitehouse 59’’)
SUBS: Davis, Cook, Russell, Pollock
BOOKED: Hendrie 25’’ Hewitt 56’’
REF: Nick Kinseley
ATT: 4,132 (383 Orient supporters)