Which series is more tough for a test batsman

[vidiq]

Scoring runs at a healthy average in a 2 match series Vs scoring runs at a healthy average in a 5 match series

 

[DrWolverine]

It is obviously more challenging to sustain a high batting average when playing a greater number of Tests.

 

[vidiq]

Kane Williamson in away series since 2016

 

[subshakerz]

It is obviously more challenging to sustain a high batting average when playing a greater number of Tests.

I think it doesn't matter.

 

[Patience and Accuracy+Gut]

On consistent series, for a truly great player, 2 match series is tougher. A great player is more likely to figure out the conditions in 5 match series than 2 match series and perform.

 

[Thala_0710]

For good/great batsmen 5 matches are definitely easier. You are very likely to get a couple of hundreds once they've figured out the conditions and bowling.
For the average/below average batsman I'd say it's around equalish or slightly tougher to sustain 5 games. In that case they would get worked out by the quality bowlers.

 

[shortpitched713]

Depends on your definition of "high". But an average some arbitrary amount higher than your actual skill level would of course be harder to maintain the longer the series is.