Well honestly, I would say "No". It is like English, where one is not able to identify which verbs are irregular by judging solely the phonetic aspect.
To this extent, a good German dictionary would quote down three forms after a strong verb:
1) the present tense (Präsens) form of the third personal singular, i.e., conjugated form of "er / es / sie";
2) the simple past tense (Präteritum) form of the first and third personal singular, i.e., conjugated form of "ich" and "er / es / sie"; and,
3) the past participle (Partizip Perfekt).
By referring to those three quoted forms, Readers will then be able to well apply such conjugated forms.
I believe that such matters also happen in English, where we usually memorize those three forms for an irregular verb. For instance,
to eat -- eats / ate / eaten;
to drink -- drinks / drank / drunk;
to sleep -- sleeps / slept / slept (as in your example).
Good day / Schönen Tag.