Dublin - Joe Schmidt and Eddie Jones have followed similar career paths from teaching to becoming two of the most highly-regarded coaches in world rugby, but the Ireland and England bosses could hardly be more different characters.
The studious Schmidt will pit his wits against Jones, the master of the quick one-liner, for the final time in the Six Nations on Saturday in a tantalising opening game for both sides.
Ireland head coach Schmidt, formerly an English teacher, steps down after the World Cup later this year while it could also be the final Six Nations campaign for his Australian counterpart, who once taught geography, as England boss.
Schmidt, 53, spoke last week of how he will miss going into the dressing room after a match and seeing the players having "left everything out on the pitch".
However, woe betide anyone who has not met his high standards.
"He (Schmidt) is a hard task master but at the same time very attentive," Irish Rugby Football Union chief executive Philip Browne told AFP.
"He has great human resource skills and he regards rugby as much about managing people off the pitch as the impact they have on it."
Jones too drives his players hard but will either try to ease the pressure on them from the media or throw verbal "grenades" at opposing teams and coaches in the lead-up to matches.
The Ireland game prompted 59-year-old Jones to lob one into Schmidt's lap just before they met with the media at the Six Nations launch last week by saying Ireland could expect "brutality" from his side on Saturday as they seek to avenge two painful successive defeats.
Schmidt, whose side denied England consecutive Grand Slams - defeating them in Dublin and last year clinching the Grand Slam themselves with victory at Twickenham - laughed it off as he did with Jones's remark that Ireland's World Player of the Year Johnny Sexton "has the batphone to the referee".
"He's always incredibly hard to read, Eddie," said Schmidt.
"It keeps it fresh, it does keep it entertaining."
Schmidt will not be one to chuck grenades at the opposition as game time approaches and says he ignores most of these comments.
"All I can keep doing is keep my head down and try and support the players as well as I can," he said on Thursday.
"It does not distract me as it is not immediately relevant."
Schmidt added at the Six Nations launch: "Eddie will create his own strategy (for the match). I have great respect for him as a strategist."
Schmidt suggests he has been on the edge of all the Irish success over the past few years.
Browne, though, is not restrained by such inhibitions when assessing his strengths.
"His attention to detail, his attitude that it is all about the player as a person," Browne told AFP.
"He has a holistic view of the game."
15 Robbie Henshaw, 14 Keith Earls, 13 Garry Ringrose, 12 Bundee Aki, 11 Jacob Stockdale, 10 Johnny Sexton, 9 Conor Murray, 8 CJ Stander, 7 Josh van der Flier, 6 Peter O'Mahony, 5 James Ryan, 4 Devin Toner, 3 Tadhg Furlong, 2 Rory Best (captain), 1 Cian Healy
Substitutes: 16 Sean Cronin, 17 Dave Kilcoyne, 18 Andrew Porter, 19 Quinn Roux, 20 Sean O'Brien, 21 John Cooney, 22 Joey Carbery, 23 Jordan Larmour
15 Elliot Daly, 14 Jonny May, 13 Henry Slade, 12 Manu Tuilagi, 11 Jack Nowell, 10 Owen Farrell (captain), 9 Ben Youngs, 8 Billy Vunipola, 7 Tom Curry, 6 Mark Wilson, 5 George Kruis, 4 Maro Itoje, 3 Kyle Sinckler, 2 Jamie George, 1 Mako Vunipola
Substitutes: 16 Luke Cowan-Dickie, 17 Ellis Genge, 18 Harry Williams, 19 Courtney Lawes, 20 Nathan Hughes, 21 Dan Robson, 22 George Ford, 23 Chris Ashton