private void buttonDelete_Click(object sender, EventArgs e)
        {
            DialogResult confirm = MessageBox.Show("Matchup akan didelete, Apakah anda yakin?", "Confirm", MessageBoxButtons.YesNo);

            if (confirm == System.Windows.Forms.DialogResult.Yes)
            {
                int    matchupSelectedIndex = dataGridViewMatchup.CurrentCell.RowIndex;
                string selectedMatchupId    = dataGridViewMatchup.Rows[matchupSelectedIndex].Cells[0].Value.ToString();

                selectedMatchup = Matchups.SelectMatchup(selectedMatchupId);

                List <MatchupEntries> pair = Matchups.GetEntries(selectedMatchup);
                selectedMatchupEntry1 = pair[0];
                selectedMatchupEntry2 = pair[1];

                MatchupEntries.Delete(selectedMatchup, selectedMatchupEntry1.Team);
                MatchupEntries.Delete(selectedMatchup, selectedMatchupEntry2.Team);

                Matchups.DeleteMatchup(selectedMatchup);

                MessageBox.Show("Delete successful.");
            }
            else
            {
                MessageBox.Show("Delete matchup canceled.");
            }
        }