There are a number of interesting cases of "delayed" damage to engines. A recent case led to three RTO's after boroscope inspections supposedly revealed no engine damage following a birdstrike. Each time the aircraft accelerated for take off there were compressor stalls and an RTO. Net result a new engine was installed and an interesting public relations problem for the airline.
This is not an isolated case. The lesson is to be wary following a bird strike. Visual inspections without a boroscope may not be sufficient and even the boroscope may not reveal all internal damage.