Calculate average of last two outcomes of last two head-to-head clashes

I've got a spreadsheet with basketball results. the columns represent date, home team, away team, margin (given from home team perspective). I want to create a column that calculate the average of the last two clashes between the two teams.

Example
Date Home Away Result ave. of last 2
24th may d b. 13

I need a value in the same row that looks for the last two games between these two teams

6th april d b 36
12 may b d -17

and calculate the average of these results. The tricky bit is that the returned average must be from the perspective of the current home team (team d won the first match by 36 points and the second by 17). The value should be 26.5

Thanks in advance

lastclash.xlsx

Hey that didn't quite seem to work. As I mentioned the correct value in E16 should be 26.5. I tried it again and have created four columns each with the result of the match from each team's perspective. If I use averageifs, it will return the average of all games between the two teams, but I want to limit it to the last two.

any ideas?
lastclash.xlsx

Pl see attached file.