The moment Zaheer Khan stopped dead in his follow-through and bent down to feel his right hamstring, an eloquent pause hung in the media room. It wasn't asked, but everyone understood the question: was this going to turn out to be the defining moment of the match, or of the series, so adroitly built up as the unofficial Test championship decider?

Despite never looking at his sharpest, Zaheer had been the soul of India's bowling attack on an absorbing first day during which neither wickets nor runs came easily. With Praveen Kumar swinging it too much to secure an edge, and Ishant Sharma not finding the length that English conditions warrant, Zaheer had to carry the day, and he did so by working his way through like a chess master. The England openers were drawn in to their dismissals.

It is no secret that Zaheer enjoys bowling to left-hand batsmen and while much of the pre-series talk had focused on his contest with Andrew Strauss, who has been seen as fallible to left-arm swing bowling, it was Alastair Cook he snared first, with one that held its course after several that moved either way. Strauss was then baited by a sucker short ball wide of off stump, which he top-edged to deep-backward square leg.

That these dismissals were replicas from 2007 - Cook at Trent Bridge, Strauss at The Oval - pointed to a design from a seasoned craftsman.

Jonathan Trott and Kevin Pietersen then built a partnership, but Zaheer returned with the aging ball, and wobbled it enough to draw an ugly flail from Pietersen and a genuine edge from Trott, before hobbling off.

Injuries are an inescapable reality that cricketers, and their teams, must live with; and fast bowlers, whose day job comprises the most unnatural contortions of the human body, are particularly susceptible.

The cold weather is unkind too to the hamstring and it comes under further stress when a left-arm quick bowler switches to round the wicket, as Zaheer often does. So, if the worst fears about Zaheer come to pass, it is perhaps down to wretched luck. There is, however, a pattern to Zaheer's mid-match breakdowns that is impossible to ignore.

In 2003, he raised Indian hopes with an inspired spell in Brisbane before sitting out the Adelaide Test and bailing out in the middle of the Melboune Test, leaving India with three frontline bowlers. A couple of months later, during India's tour of Pakistan, he once again limped off the field during the Multan Test that Indian went on to win. He returned home when it became obvious that the muscle that he had pulled wasn't going to heal in time for the final Test. In 2007-08, a heel injury restricted his tour of Australia to only one Test. Last year, he withdrew from the Test tour of Sri Lanka, and missed the opening Test in South Africa.

This leaves only two away series of significance - South Africa in 2006-07, and England in 2007 - that he has been able to complete in recent years. That the career of a bowler who has grown so skillful should be defined by injuries is depressing.

Zaheer knows his body better than anyone else and he has perhaps reconciled himself to the limitations it imposes on him. Some fast bowlers are blighted by chronic injuries. Shane Bond's body never allowed him to make full use of the gift he had been granted: the ability to bowl fast with a clean action. Ian Bishop looked a worthy heir to Michael Holding before a stress fracture of the back terminated his career. And Munaf Patel has embraced the life of a trundler after beginning with thunderbolts.

But even from the height of the media box at Lord's it was impossible not to notice the girth around Zaheer's waist. He hadn't played a Test since January and had had no competitive cricket in six weeks. It was apparent that he was feeling his way back in the practice match against Somerset, but that he chose to rest in the second innings perhaps told a story. That he managed to rouse himself for a contest at Lord's was proof of the mastery he has acquired over his craft. But Michael Holding, who was on air when Zaheer aborted his over, remarked straightaway he wasn't surprised because Zaheer hadn't looked match fit. While India remain optimistic about his chances of bowling in the second innings, the fate of this Test now rests on how well the rest of the bowling attack copes with the absence of their leader in this innings.

Sambit Bal is the editor of ESPNcricinfo