Fit-again Cummings was restored to the starting line-up as Cherries' League One play-off hopes suffered another setback at Dean Court on Saturday.
Defeat at the hands of lowly Tranmere extended to seven Cherries' winless run as Lee Bradbury's men were sunk by Adam McGurk's strike deep into stoppage time.
Cherries had looked set to claim a precious point after Danny Ings had come off the bench to equalise in the first minute of added time before McGurk pounced in the dying seconds.
Cummings told the Daily Echo: Our first-half performance was very poor and we didn't play at a high enough tempo. We were much better in the second half but were disappointed to concede a second goal so late.
We haven't had the rub of the green recently and a few decisions have gone against us. At times, our finishing hasn't been as good as it could have been. But, in the main, our performances have been good although we haven't got our just desserts.
If there is something to hold on to and be positive about it is that our destiny is still in our hands. We've got to count ourselves lucky for that, but we've got to forget the past seven games and concentrate on the next five.
Confidence is fragile and we know we are not having a good spell at the moment. Overall though, our form is not too bad and we can still get to where we want to be. We have never got ahead of ourselves and are a resilient group. We will come through this.
Experienced campaigner Cummings endured a play-off near-miss with Cherries in 2005 and is determined to ensure the younger members of Bradbury's squad are made aware of how infrequently the opportunities can arise.
The 30-year-old added: It is all about seizing the moment because these opportunities don't come around too often. When I broke my leg in 2005, we had a fantastic chance to reach the play-offs. We under-achieved then and the chance hasn't come around again until now.
It is a pressure situation and the senior players have a responsibility to help the younger lads through this sticky spell. We have to do it quickly because otherwise it could be taken out of our hands.
Whatever happens, it won't be for a lack of effort. This group of players works harder and is more conscientious than any other I have been involved in. As a group, we have had a lot to contend with and so have the supporters.
We have got to create a siege mentality because we are all in this together. We are having a bad run of results but we will fight to the death and have five games to put it right.