On page one, we showed a perfectly executed endplay. Things do not always go so well. The biggest fear is third seat will take a trick then lead the same suit back through the maker. This could result in a euchre. (Something to keep in mind when on defense)
The player in south position, having dealt, gets to pick the ace of clubs. Holding right, ace and king, he's not worried about making his point. By discarding the king of hearts, he will have a two-suited hand.
West gets things started by leading the ace of hearts. North follow suit with the 10. East rids his hand of a useless 9 of spades. The maker/dealer in south trumps with the king. Their team now has one trick with one trump played.
Looking to set up an endplay, the maker uses the lowly 9 of diamonds. By South leading a junk card, West knew he was up to something. The biggest problem when playing with experienced players, such as was sitting in first, is that they don't want to make it easy. In fact, they would like to euchre you. West could have trumped-in but decided instead that it would be better to let the trick go by. He is hoping his partner in east will be able to take it. His hunch is correct and East takes the trick with his ace.
Now East tries leading through the maker using another diamond. The maker overtakes the jack with his queen. West seizes the opportunity and plays the left. However, the maker is not concerned. After all, he now holds the two top trump.
While not by the book, in the 'end' the play worked.
As with most euchre hands, all you can do is play the hand correctly and hope 'lady luck' is in a good mood.