The hosts were dumped out of the FA Trophy after a 2-0 loss to Maidenhead United, while the Spitfires advanced to the last 16 after recording a 1-0 win over Braintree Town.
Match preview
Despite putting five past Uxbridge in the third round of the FA Trophy, Dagenham's previous prolific tendencies counted for nought on Saturday, as Maidenhead advanced to the last-16 of the competition at the expense of Daryl McMahon's team.
Shawn McCoulsky took all of two minutes to propel Maidenhead into the lead before winning a penalty after being felled by Elliot Johnson, and Charlee Adams made no mistake from 12 yards to give the visitors a healthy two-goal cushion just before the interval.
Elimination from the EFL Trophy means that Dagenham only have their promotion charge to think about for the remainder of the campaign, and a 2-0 success over Aldershot Town last week means that the Daggers' playoff destiny is still in their own hands - sitting seventh in the table with 38 points from their 24 matches.
Having spent seven years outside of the Football League, Dagenham are itching for a return to the big time but are still looking over their shoulder, as Bromley, Wealdstone and upcoming opponents Eastleigh are all within touching distance.
Six out of the hosts' last eight fifth-tier encounters have ended in victory, but the two outliers in that sequence were home defeats in front of their own supporters, and Eastleigh have all the motivation they need to inflict another Victoria Road loss upon their seventh-tier hosts.
In contrast, Eastleigh's dreams of FA Trophy glory are still alive following a 1-0 triumph over Braintree Town in front of their own fans on Saturday, with Danny Whitehall's cannon of an effort striking the underside of the crossbar before going in in the dying embers.
Victory in the cup was the perfect tonic to a 3-1 loss to Wealdstone in league action two weekends ago, which derailed Lee Bradbury side's playoff bid that little bit more as they sit 10th in the rankings, but only three points separate the Spitfires from their upcoming opponents.
The festive season has not been a kind one to Eastleigh, who can only boast two wins from their last eight National League contests, while their abysmal stretch of away form has seen them fail to win any of their last 11 fifth-tier games on the road - losing five of their last six.
Dagenham and Eastleigh played out a 1-1 draw in August's meeting at the Silverlake Stadium, and only one of the visitors' most recent four games versus the Daggers has ended in victory, although that was a narrow 1-0 triumph at Victoria Road last season.
Dagenham & Redbridge National League form:
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Dagenham & Redbridge form (all competitions):
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Eastleigh National League form:
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Team News
Dagenham welcomed right-back Sam Ling into the first XI for the loss to Maidenhead, three months after the 26-year-old had suffered a broken foot, but fellow full-back Johnson saw red for bringing down McCoulsky in the FA Trophy.
With Johnson now suspended, Josh Taylor should be given the nod on the left-hand side of the backline, but McMahon has no other concerns to report from their most recent outing.
Josh Walker - who came up with the game-winning double versus Aldershot - was only used off the bench in the FA Trophy, but he can expect a quick recall to the first XI here.
Meanwhile, Eastleigh striker Whitehall will not have the chance to build on his eye-catching winner in the EFL Trophy, as he is suspended for this game after picking up his 10th yellow card of the season against Wealdstone.
The visitors have also confirmed a trio of long-term absentees, with Brennan Camp and Michael Kelly each facing at least two months out with hamstring injuries, while Ryan Hill is facing a similar period of rehabilitation with a knee injury.
A lack of full-back options means that Corey Panter - a centre-back by trade - should be given the nod on the right, while Tristan Abrahams can expect to deputise for the suspended Whitehall in the final third.
Dagenham & Redbridge possible starting lineup:
Justham; Ling, Onariase, Longe-King, Taylor; Sagaf, Rance, Robinson, Weston; Walker, McCallum
Eastleigh possible starting lineup:
McDonnell; Panter, Martin, Magahoma, Harper; Rutherford, Cisse, Atangana, Carter; A. Lloyd, Abrahams
We say: Dagenham & Redbridge 2-0 Eastleigh
With top scorer Whitehall forced to watch this one from the naughty step, an Eastleigh side who have continuously failed to make waves away from home should be in for another miserable outing on the road.