Meaning of "against"

In the example sentence "against" is a preposition and against the conventional meaning here it comes to suggest the meaning of " next to and touching or being supported by (something)Cf.

It would save space if we put the bed against the wall. (dictionary.cambridge.org)

So "against" here goes to mean "supported by".

Here’s a definition of against from AHD that may suit your purposes:

10. To the account or debt of: drew a check against my bank balance. https://www.ahdictionary.com/word/search.html?q=against

Consider “ Each futures exchange has specific delivery and storage requirements that must be met. For example, at the CME, exchange-approved warehouses are the only entities and locations that can deliver against a futures contract.” From Investopedia.

An alternative to “against” here would be in response to the presentation of.