Author: Flowingcloud
Please contact Flowingcloud if there are any typos, issues, or input. All feedback is welcome!
Introduction
Welcome back to part 2 of the series. The last post was relatively simple, but this time, there will be a more complex situation. The topics are still relatively related, but this time, there is more to the story than sanshoku. This post will focus on two main topics. Since there weren’t many decisions to make, certain posts are a bit more dense than usual. Breaking away from tenpai early, as well as keeping the hand available for all opportunities possible. Newer players should be able to take away a lot from this example, while intermediate players should try to follow step by step to see if you would make the same decisions.
Today, we’ll be following gameplay by a relatively well-known mahjong player: Hinata Aiko. Hinata-pro has been a M-Leaguer for several seasons and she is trying to climb back to A2 currently. Her play has stablized a lot during the past year and she is currently one of the most solid female pros in Saikouisen right now.
Gameplay
Match: https://www.youtube.com/watch?v=Ww_nk7aMEOQ [Channel membership required]
Clip: https://youtu.be/E9nCFX0VZNQ
Ruleset: Saikouisen (aka-nashi; 10/30 uma)
Player: Hinata Aiko
Situation: We’re in East 4 of the first set of league games. Hinata (non-dealer) is currently in first place by 2,100 points on second place and 8,800 points on third place. While being first currently is good, Hinata-pro wants to expand her lead even further to secure her first. After cutting the standard honors and edge tile, we are presented with a decision on turn 4.
turn 4
We’ll be starting at Turn 4 since the first three turns were pretty standard efficiency tile cuts. Hinata has now drawn the 5p and needs to make a decision. She can clearly see the potential 789 sanshoku that is forming with both the 
and 
blocks already connected, so the 7m is never being cut since we are leaving the tile for sanshoku and drawing 6m also allows for the 5m dora acceptance. The shapes might be somewhat diffcult to process, but the decision is between 7s and 5p. The 7s is the extra tile since the souzu shape is 
. Although the 5p is a strong middle tile, the 7s allows for iippeikou (identical sequences) chance, as well as a slight chance for iitsu (straight).
turn 5
Hinata obtains tenpai on the 4s draw, however, the wait would only be a 3-7s shanpon wait riichi with only three tiles visible of the wait left. Riichi-nomi for a guaranteed 1,300 points (2,000 points via tsumo) would be extremely sad with how much this hand could potentially be worth. Since we are still in the first row and improving the hand can be easily done, not taking tenpai initially and changing the wait for more value is much more valuable.
The hand is extremely flexible with many upgrades to both iitsu and sanshoku both available, or even just a simple upgrade to a pinfu hand or a kanchan that contains a dora (57m). Your draw back into tenpai is extremely wide and any souzu would give tenpai. If you look at the image below, and souzu draw would give tenpai again.
(East is just a placeholder for the 3s discard. Please look at the East column.)
The most ideal draw would generally be 1s, 2s, 8m, and 9m:
1s draw: 13s kanchan for guaranteed iitsu (straight) in souzu
2s draw: 147s three-sided wait for iitsu chance in souzu
8m draw: 69m wait for 789 sanshoku chance
9m draw: 8m wait for guaranteed 789 sanshoku
Additonally, there are many other draws that make a strong ryanmen or three-sided wait for an easy riichi pinfu, and the 5m draw for a dora kanchan is an acceptable riichi. Even, the last 7s would not even be bad for a furiten 6-sided wait.
Shape:
Wait:
turn 7
Three turns later, Hinata gets tenpai by drawing one of the “ideal” draws and now has a guaranteed 789 sanshoku. From here, there is no real need to improve the hand any further, so this is a basic textbook riichi.
turn 13
Turn 13: Ron 8m off Ishizaki (toimen)
Eventually, Hinata atamahanes her shimocha (player right) and rons 8m off Ishizaki-pro as he was sliding his 
→ 
to accept dora for his own 567 sanshoku. Although there was no ura, 5,200 points directly off second place is a huge 10,400 point swing, and now, Hinata is securely in first place entering the South round.
Conclusion
A strong mahjong player will usually pass up an early tenpai if their wait is bad and does not have much value. Just because a player tenpai achieves tenpai, they do not need to “click the riichi button” immediately. By not taking tenpai initally, an experienced player can often build a stronger hand and capitalize on the full potential of a hand. In this case, Hinata-pro was still in the first row of discards, leaving plently time for her hand to improve. Learning the timing to break tenpai, and not doing it too late, is a relatively hard balance. Generally speaking though, first row is usually early enough to break tenpai (and going back to isshanten) to build more value. If you incorporate this into your gameplay and practice doing so, this is what sets normal players and strong players apart!