I have fought the good fight (τον καλον αγωνα ηγωνισμα). Perfect middle indicative of αγωνιζομα, a favourite figure with Paul (1. Corinthians 9:25; Colossians 1:29), with the cognate accusative αγωνα (Philippians 1:27; Philippians 1:30, etc.). The "fight" is the athletic contest of his struggle for Christ.
I have finished the course (τον δρομον τετελεκα). Perfect active indicative of τελεω. He had used this metaphor also of himself to the elders at Ephesus (Acts 20:24). Then the "course" was ahead of him. Now it is behind him.
I have kept the faith (την πιστιν τετηρηκα). Perfect active indicative again of τηρεω. Paul has not deserted. He has kept faith with Christ. For this phrase, see Revelation 14:12. Deissmann (Light, etc., p. 309) gives inscriptions in Ephesus of a man who says: "I have kept faith" (την πιστιν ετηρησα) and another of a man of whom it is said: "He fought three fights, and twice was crowned."