India's seven-wicket win against Sri Lanka at Headingley ended a sequence of seven straight games in this World Cup that had been won by the side batting first. It was the second such sequence of the tournament: between June 20 and June 25, teams batting first had also won seven in a row. All of this means that of the last 20 games played in the tournament, 16 have been won by the team batting first. The exceptions during this period are: Pakistan's six-wicket win against New Zealand; South Africa's nine-wicket win against Sri Lanka; Pakistan's three-wicket win against Afghanistan; and India's win on Saturday.
In the first three weeks of the tournament, when the weather was quite inclement and the pitches fresher, the numbers were very even - 11 wins for the team batting first and 10 for the team chasing in 21 completed matches. But with the pitches wearing and the weather drying out, batting first seems to have given a definite advantage to teams. In fact, in the entire history of World Cup matches, there has only been one other streak of the chasing teams losing more than six in a row in a single edition: in 1983, when the first seven games all went to the team batting first.
The stats in England in the four years leading up to the World Cup were quite the opposite. The pitches were generally flat and excellent for batting, and remained so throughout the 100 overs, giving the chasing team the advantage. Between the last two World Cups, chasing teams had a 32-20 win-loss record in ODIs in England. England were dominant either way, but their record in chases - 20 wins, three losses - was much better than when batting first - 14 wins, six losses.
In the World Cup though, the pitches have generally been slower and not as good for batting, resulting in the teams batting second struggling to chase down totals. The run rate for teams batting second has dropped from 6.08 in the four-year period before the World Cup, to 5.47 in the World Cup.
In fact, the 2019 World Cup is turning out to be one of the most skewed, in terms of wins for the teams batting first (27-14). Only once in World Cup history have the teams batting first won more often and that was back in 1987, when they had a 19-8 record. The last three World Cups were, in fact, almost even in terms of win-loss records for teams batting first and teams chasing.
In the first half of the current World Cup, the wet weather and fresher pitches meant captains were wary about batting first after winning the toss: out of the first 21 completed games, teams chose to bat only four times after winning the toss. In those games, they had a 2-2 win-loss record. Since then, in the last 20 games, they have batted first 15 times and picked up 12 victories. This year's overall win-loss record for teams winning the toss and batting is the most skewed among all World Cups.
The three remaining matches of World Cup 2019 will be played at Old Trafford, Edgbaston and Lord's, venues where teams batting first have dominated. Overall in the tournament, they have a 11-2 record; in the second half of the tournament, it improves to 9-1, with the only loss being New Zealand's defeat against Pakistan at Edgbaston.
Fresh pitches at all three venues will probably give the chasing teams a better chance in the final week, but if the weather stays clear, teams winning the toss will surely want to bat first. Going by these numbers, the teams chasing will have more than just scoreboard pressure in a knockout game working against them.