请教GAMES中的用词

(1)  Ruth runs an earlier leg of the race than Peggy runs.

(2)  J is inspected on an earlier day than Q is inspected.

请问：对“an”的理解，如以（1）为例是指R在P的前“一”棒呢，还是指R在P之前但不强调“一棒”。

谢谢大家，盼指教。