How skillful was Karna?

Commenting is disabled. However just wanted to bring this to your notice - When you say this:

If Karna was not great warrior then why "lord Krishna" directed unethical way to Arjuna to kill karna (when Karna chariot's wheel sank into earth and then Karna stepped out to remove wheel and requested to suspend war but lord Krishna then advised Arjuna to kill him considering this as best time to take victory ..I consider Karna was wrong morally by supporting Duryodhan but no doubt he was great warrior and invincible otherwise Krishna never direct such immoral step to kill someone.

This is the TV version and maybe that Mrutyunjaya Kumar version of Mahabharatha. In vyaasa bharatha, Karna Parva, Karna Vadha Parva, Adhyaya 067, Shloka 007 says this:

तं समीक्ष्य ततः कर्णो ब्रह्मास्त्रेण धनञ्जयम् । अभ्यवर्षत्पुनर्यत्नमकरोद्र्थसर्जने ॥ ००८ ॥

तदस्त्रमस्त्रेणावार्य प्रजहारास्य पाण्डवः ॥००८॥

Karna then looked at Arjuna, stopped his effort to free his chariot, loaded Brahmastra to his bow and fired it towards Arjuna. The Pandava defended that astra with his own astra.

If you are still not satisfied with this translation, look for this Shloka in Vyasa Mahabharata or any authentic version of Mahabharatha which is not adultered for selfish motive. Also, feel free to translate it to your own language to understand. I do not have great Sanskrit knowledge.