Jiraya sage mode + Summoning Toad + his toad Techniques = winner heheheh
hmm.... sry but jiraiya i doubt will stand a chance in summonings fights since....
Jiraiya= 3 bigs frogs+2little frogs+2sages frogs when in sage mode
Oro= Thousands of snakes(used when fought 4 tails naruto)+ Manda(and who knows if its possible to get manda v2.)+ Yamata no orochi which is like 4 big frogs together it is said to be as strong as any bijuu.......
as far as we have seen if it wasn't for Tsunade and Katsuyu...... Gamabunta would have been owned by manda during their fight.......
Sage mode is beaten by oro's endurance+white snake form........ Kusanagi IS ABLE TO PIERCE THROUGHT JIRAIYA....... If Kusanagi Sword is able to hurt enma in DIAMOND (HARDEST SH!T EVER) STAFF FORM then it will surely be able to get through jiraiya sage mode skin.
HONESTLY THE ONLY WAY I CAN SEE JIRAIYA WINNING IS BY USING FROG GENJUTSU....... AND THAT IF JIRAIYA MANAGES TO SUMMON THE FROGS AND TO LET THEM SING WILD..... IF NOT JIRAIYA IS MORE THAN DEAD....
and no..... I'm not a oro-fanboy even more jiraiya with pain and tsunade are my favorites but sometimes even our own favorites are in a BAD-MATCHUP